diff --git a/.travis.yml b/.travis.yml
index 6337236621..bfd530288e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,3 +20,13 @@ matrix:
       script:
         - python3 ./source/server-discovery-and-monitoring/tests/errors/generate-error-tests.py
         - cd source && make && git diff --exit-code
+
+    - name: "Unifed Test Format schema checks"
+      dist: xenial
+      language: python
+      python:
+        - 3.7
+      install:
+        - npm install -g ajv-cli
+      script:
+        - cd source/unified-test-format/tests && make
diff --git a/source/unified-test-format/schema-1.0.json b/source/unified-test-format/schema-1.0.json
new file mode 100644
index 0000000000..3ce636c952
--- /dev/null
+++ b/source/unified-test-format/schema-1.0.json
@@ -0,0 +1,286 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+
+  "title": "Unified Test Format",
+  "type": "object",
+  "additionalProperties": false,
+  "required": ["description", "schemaVersion", "tests"],
+  "properties": {
+    "description": { "type": "string" },
+    "schemaVersion": { "$ref": "#/definitions/version" },
+    "runOnRequirements": {
+      "type": "array",
+      "minItems": 1,
+      "items": { "$ref": "#/definitions/runOnRequirement" }
+    },
+    "createEntities": {
+      "type": "array",
+      "minItems": 1,
+      "items": { "$ref": "#/definitions/entity" }
+    },
+    "initialData": {
+      "type": "array",
+      "minItems": 1,
+      "items": { "$ref": "#/definitions/collectionData" }
+    },
+    "tests": {
+      "type": "array",
+      "minItems": 1,
+      "items": { "$ref": "#/definitions/test" }
+    }
+  },
+
+  "definitions": {
+    "version": {
+      "type": "string",
+      "pattern": "^[0-9]+(\\.[0-9]+){1,2}$"
+    },
+
+    "runOnRequirement": {
+      "type": "object",
+      "additionalProperties": false,
+      "minProperties": 1,
+      "properties": {
+        "maxServerVersion": { "$ref": "#/definitions/version" },
+        "minServerVersion": { "$ref": "#/definitions/version" },
+        "topologies": {
+          "type": "array",
+          "minItems": 1,
+          "items": {
+            "type": "string",
+            "enum": ["single", "replicaset", "sharded", "sharded-replicaset"]
+          }
+        }
+      }
+    },
+
+    "entity": {
+      "type": "object",
+      "additionalProperties": false,
+      "maxProperties": 1,
+      "minProperties": 1,
+      "properties": {
+        "client": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id"],
+          "properties": {
+            "id": { "type": "string" },
+            "uriOptions": { "type": "object" },
+            "useMultipleMongoses": { "type": "boolean" },
+            "observeEvents": {
+              "type": "array",
+              "minItems": 1,
+              "items": {
+                "type": "string",
+                "enum": ["commandStartedEvent", "commandSucceededEvent", "commandFailedEvent"]
+              }
+            },
+            "ignoreCommandMonitoringEvents": {
+              "type": "array",
+              "minItems": 1,
+              "items": { "type": "string" }
+            }
+          }
+        },
+        "database": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id", "client", "databaseName"],
+          "properties": {
+            "id": { "type": "string" },
+            "client": { "type": "string" },
+            "databaseName": { "type": "string" },
+            "databaseOptions": { "$ref": "#/definitions/collectionOrDatabaseOptions" }
+          }
+        },
+        "collection": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id", "database", "collectionName"],
+          "properties": {
+            "id": { "type": "string" },
+            "database": { "type": "string" },
+            "collectionName": { "type": "string" },
+            "collectionOptions": { "$ref": "#/definitions/collectionOrDatabaseOptions" }
+          }
+        },
+        "session": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id", "client"],
+          "properties": {
+            "id": { "type": "string" },
+            "client": { "type": "string" },
+            "sessionOptions": { "type": "object" }
+          }
+        },
+        "bucket": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id", "database"],
+          "properties": {
+            "id": { "type": "string" },
+            "database": { "type": "string" },
+            "bucketOptions": { "type": "object" }
+          }
+        },
+        "stream": {
+          "type": "object",
+          "additionalProperties": false,
+          "required": ["id", "hexBytes"],
+          "properties": {
+            "id": { "type": "string" },
+            "hexBytes": {
+              "type": "string",
+              "pattern": "^([0-9A-Fa-f]{2})*$"
+            }
+          }
+        }
+      }
+    },
+
+    "collectionData": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["collectionName", "databaseName", "documents"],
+      "properties": {
+        "collectionName": { "type": "string" },
+        "databaseName": { "type": "string" },
+        "documents": {
+          "type": "array",
+          "items": { "type": "object" }
+        }
+      }
+    },
+
+    "expectedEventsForClient": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["client", "events"],
+      "properties": {
+        "client": { "type": "string" },
+        "events": {
+          "type": "array",
+          "items": { "$ref": "#/definitions/expectedEvent" }
+        }
+      }
+    },
+
+    "expectedEvent": {
+      "type": "object",
+      "additionalProperties": false,
+      "maxProperties": 1,
+      "minProperties": 1,
+      "properties": {
+        "commandStartedEvent": {
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "command": { "type": "object" },
+            "commandName": { "type": "string" },
+            "databaseName": { "type": "string" }
+          }
+        },
+        "commandSucceededEvent": {
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "reply": { "type": "object" },
+            "commandName": { "type": "string" }
+          }
+        },
+        "commandFailedEvent": {
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "commandName": { "type": "string" }
+          }
+        }
+      }
+    },
+
+    "collectionOrDatabaseOptions": {
+      "type": "object",
+      "additionalProperties": false,
+      "properties": {
+        "readConcern": { "type": "object" },
+        "readPreference": { "type": "object" },
+        "writeConcern": { "type": "object" }
+      }
+    },
+
+    "operation": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["name", "object"],
+      "properties": {
+        "name": { "type": "string" },
+        "object": { "type": "string" },
+        "arguments": { "type": "object" },
+        "expectError":  { "$ref": "#/definitions/expectedError" },
+        "expectResult": {},
+        "saveResultAsEntity": { "type": "string" }
+      },
+      "allOf": [
+        { "not": { "required": ["expectError", "expectResult"] } },
+        { "not": { "required": ["expectError", "saveResultAsEntity"] } }
+      ]
+    },
+
+    "expectedError": {
+      "type": "object",
+      "additionalProperties": false,
+      "minProperties": 1,
+      "properties": {
+        "isError": {
+          "type": "boolean",
+          "const": true
+        },
+        "isClientError": { "type": "boolean" },
+        "errorContains": { "type": "string" },
+        "errorCode": { "type": "integer" },
+        "errorCodeName": { "type": "string" },
+        "errorLabelsContain": {
+          "type": "array",
+          "minItems": 1,
+          "items": { "type": "string" }
+        },
+        "errorLabelsOmit": {
+          "type": "array",
+          "minItems": 1,
+          "items": { "type": "string" }
+        },
+        "expectResult": {}
+      }
+    },
+
+    "test": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["description", "operations"],
+      "properties": {
+        "description": { "type": "string" },
+        "runOnRequirements": {
+          "type": "array",
+          "minItems": 1,
+          "items": { "$ref": "#/definitions/runOnRequirement" }
+        },
+        "skipReason": { "type": "string" },
+        "operations": {
+          "type": "array",
+          "items": { "$ref": "#/definitions/operation" }
+        },
+        "expectEvents": {
+          "type": "array",
+          "items": { "$ref": "#/definitions/expectedEventsForClient" }
+        },
+        "outcome": {
+          "type": "array",
+          "minItems": 1,
+          "items": { "$ref": "#/definitions/collectionData" }
+        }
+      }
+    }
+  }
+}
diff --git a/source/unified-test-format/schema-testing-example.json b/source/unified-test-format/schema-testing-example.json
new file mode 100644
index 0000000000..eabb41674f
--- /dev/null
+++ b/source/unified-test-format/schema-testing-example.json
@@ -0,0 +1,63 @@
+{
+  "tests": [
+    {
+      "description": "valid because error:true and result has only expected fields",
+      "operations": [
+        {
+          "object": "collection",
+          "name": "runCommand",
+          "error": true,
+          "result": {
+            "errorContains": "string"
+          }
+        }
+      ]
+    },
+    {
+      "description": "valid because error == false. result can be any type (non-object)",
+      "operations": [
+        {
+          "object": "collection",
+          "name": "operation",
+          "error": false,
+          "result": 1
+        }
+      ]
+    },
+    {
+      "description": "valid because error == false. result can be any type (object)",
+      "operations": [
+        {
+          "object": "collection",
+          "name": "operation",
+          "error": false,
+          "result": {
+            "foo": "bar"
+          }
+        }
+      ]
+    },
+    {
+      "description": "valid because error != true. result can be any type (non-object)",
+      "operations": [
+        {
+          "object": "collection",
+          "name": "operation",
+          "result": 1
+        }
+      ]
+    },
+    {
+      "description": "valid because error != true. result can be any type (object)",
+      "operations": [
+        {
+          "object": "collection",
+          "name": "operation",
+          "result": {
+            "foo": "bar"
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/Makefile b/source/unified-test-format/tests/Makefile
new file mode 100644
index 0000000000..2df2261eb5
--- /dev/null
+++ b/source/unified-test-format/tests/Makefile
@@ -0,0 +1,21 @@
+SCHEMA=../schema-1.0.json
+
+.PHONY: all invalid valid-fail valid-pass HAS_AJV
+
+all: invalid valid-fail valid-pass
+
+invalid: HAS_AJV
+	@# Redirect stdout to hide expected validation errors
+	@ajv test -s $(SCHEMA) -d "invalid/*.yml" --invalid > /dev/null && echo "invalid/*.yml passed test"
+
+valid-fail: HAS_AJV
+	@ajv test -s $(SCHEMA) -d "valid-fail/*.yml" --valid
+
+valid-pass: HAS_AJV
+	@ajv test -s $(SCHEMA) -d "valid-pass/*.yml" --valid
+
+HAS_AJV:
+	@if ! command -v ajv > /dev/null; then                \
+	    echo 'Error: need "npm install -g ajv-cli"' 1>&2; \
+	    exit 1;                                           \
+	fi
diff --git a/source/unified-test-format/tests/README.rst b/source/unified-test-format/tests/README.rst
new file mode 100644
index 0000000000..dd422f7f02
--- /dev/null
+++ b/source/unified-test-format/tests/README.rst
@@ -0,0 +1,39 @@
+=========================
+Unified Test Format Tests
+=========================
+
+.. contents::
+
+----
+
+Introduction
+============
+
+This directory contains tests for the Unified Test Format's schema and test
+runner implementation(s). Tests are organized in the following directories:
+
+- ``invalid``: These files do not validate against the schema and are used to
+  test the schema itself.
+
+- ``valid-pass``: These files validate against the schema and should pass when
+  executed with a test runner.
+
+- ``valid-fail``: These files validate against the schema but should produce
+  runtime errors or failures when executed with a test runner. Some do so by
+  violating the "SHOULD" and "SHOULD NOT" guidance in the spec (e.g. referencing
+  an undefined entity).
+
+Validating Test Files
+=====================
+
+JSON and YAML test files can be validated using `Ajv <https://ajv.js.org/>`__
+and a schema from the parent directory (e.g. ``schema-1.0.json``).
+
+Test files can be validated individually like so::
+
+    ajv -s ../schema-1.0.json -d path/to/test.yml
+
+Ajv can also be used to assert the validity of test files::
+
+    ajv test -s ../schema-1.0.json -d "invalid/*.yml" --invalid
+    ajv test -s ../schema-1.0.json -d "valid-*/*.yml" --valid
diff --git a/source/unified-test-format/tests/example-insertOne.json b/source/unified-test-format/tests/example-insertOne.json
new file mode 100644
index 0000000000..be41f9eacb
--- /dev/null
+++ b/source/unified-test-format/tests/example-insertOne.json
@@ -0,0 +1,100 @@
+{
+  "description": "example-insertOne",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "2.6"
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "test"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "coll"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "coll",
+      "databaseName": "test",
+      "documents": [
+        {
+          "_id": 1
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "insertOne",
+      "operations": [
+        {
+          "object": "collection0",
+          "name": "insertOne",
+          "arguments": {
+            "document": {
+              "_id": 2
+            }
+          },
+          "expectResult": {
+            "insertedId": {
+              "$$unsetOrMatches": 2
+            }
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "commandName": "insert",
+                "databaseName": "test",
+                "command": {
+                  "insert": "coll",
+                  "documents": [
+                    {
+                      "_id": 2
+                    }
+                  ]
+                }
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "test",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/example-insertOne.yml b/source/unified-test-format/tests/example-insertOne.yml
new file mode 100644
index 0000000000..22b27bb2f8
--- /dev/null
+++ b/source/unified-test-format/tests/example-insertOne.yml
@@ -0,0 +1,53 @@
+description: "example-insertOne"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "2.6"
+
+createEntities:
+  - client:
+      id: &client0 client0
+      observeEvents:
+        - commandStartedEvent
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name test
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name coll
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1 }
+
+tests:
+  - description: "insertOne"
+    operations:
+      -
+        object: *collection0
+        name: insertOne
+        arguments:
+          document: { _id: 2 }
+        expectResult:
+          insertedId: { $$unsetOrMatches: 2 }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              commandName: insert
+              databaseName: *database0Name
+              command:
+                insert: *collection0Name
+                documents:
+                  - { _id: 2 }
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
diff --git a/source/unified-test-format/tests/invalid/collectionData-additionalProperties.json b/source/unified-test-format/tests/invalid/collectionData-additionalProperties.json
new file mode 100644
index 0000000000..2d85093109
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-additionalProperties.json
@@ -0,0 +1,40 @@
+{
+  "description": "collectionData-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "databaseName": "foo",
+      "documents": [],
+      "foo": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-additionalProperties.yml b/source/unified-test-format/tests/invalid/collectionData-additionalProperties.yml
new file mode 100644
index 0000000000..6a2256a639
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-additionalProperties.yml
@@ -0,0 +1,26 @@
+description: "collectionData-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents: []
+    foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-collectionName-required.json b/source/unified-test-format/tests/invalid/collectionData-collectionName-required.json
new file mode 100644
index 0000000000..040dd86a1c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-collectionName-required.json
@@ -0,0 +1,38 @@
+{
+  "description": "collectionData-collectionName-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "databaseName": "foo",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-collectionName-required.yml b/source/unified-test-format/tests/invalid/collectionData-collectionName-required.yml
new file mode 100644
index 0000000000..2f20805581
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-collectionName-required.yml
@@ -0,0 +1,24 @@
+description: "collectionData-collectionName-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - databaseName: *database0Name
+    documents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-collectionName-type.json b/source/unified-test-format/tests/invalid/collectionData-collectionName-type.json
new file mode 100644
index 0000000000..676d822e5e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-collectionName-type.json
@@ -0,0 +1,39 @@
+{
+  "description": "collectionData-collectionName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": 0,
+      "databaseName": "foo",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-collectionName-type.yml b/source/unified-test-format/tests/invalid/collectionData-collectionName-type.yml
new file mode 100644
index 0000000000..a9da0e0129
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-collectionName-type.yml
@@ -0,0 +1,25 @@
+description: "collectionData-collectionName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: 0
+    databaseName: *database0Name
+    documents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-databaseName-required.json b/source/unified-test-format/tests/invalid/collectionData-databaseName-required.json
new file mode 100644
index 0000000000..7548f9d5be
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-databaseName-required.json
@@ -0,0 +1,38 @@
+{
+  "description": "collectionData-databaseName-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-databaseName-required.yml b/source/unified-test-format/tests/invalid/collectionData-databaseName-required.yml
new file mode 100644
index 0000000000..d8d6e4d571
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-databaseName-required.yml
@@ -0,0 +1,24 @@
+description: "collectionData-databaseName-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    documents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-databaseName-type.json b/source/unified-test-format/tests/invalid/collectionData-databaseName-type.json
new file mode 100644
index 0000000000..ef719bbf6a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-databaseName-type.json
@@ -0,0 +1,39 @@
+{
+  "description": "collectionData-databaseName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "databaseName": 0,
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-databaseName-type.yml b/source/unified-test-format/tests/invalid/collectionData-databaseName-type.yml
new file mode 100644
index 0000000000..27dfaafee1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-databaseName-type.yml
@@ -0,0 +1,25 @@
+description: "collectionData-databaseName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: 0
+    documents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-items.json b/source/unified-test-format/tests/invalid/collectionData-documents-items.json
new file mode 100644
index 0000000000..2916718d50
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-items.json
@@ -0,0 +1,41 @@
+{
+  "description": "collectionData-documents-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "databaseName": "foo",
+      "documents": [
+        0
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-items.yml b/source/unified-test-format/tests/invalid/collectionData-documents-items.yml
new file mode 100644
index 0000000000..6e860e896f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-items.yml
@@ -0,0 +1,25 @@
+description: "collectionData-documents-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-required.json b/source/unified-test-format/tests/invalid/collectionData-documents-required.json
new file mode 100644
index 0000000000..7b8a7ead2a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-required.json
@@ -0,0 +1,38 @@
+{
+  "description": "collectionData-documents-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "databaseName": "foo"
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-required.yml b/source/unified-test-format/tests/invalid/collectionData-documents-required.yml
new file mode 100644
index 0000000000..0452842bc7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-required.yml
@@ -0,0 +1,24 @@
+description: "collectionData-documents-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-type.json b/source/unified-test-format/tests/invalid/collectionData-documents-type.json
new file mode 100644
index 0000000000..953cabae6e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-type.json
@@ -0,0 +1,39 @@
+{
+  "description": "collectionData-documents-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "foo",
+      "databaseName": "foo",
+      "documents": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionData-documents-type.yml b/source/unified-test-format/tests/invalid/collectionData-documents-type.yml
new file mode 100644
index 0000000000..db6d8b417a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionData-documents-type.yml
@@ -0,0 +1,25 @@
+description: "collectionData-documents-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: &database0Name "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: &collection0Name "foo"
+      foo: 0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.json b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.json
new file mode 100644
index 0000000000..beef260eed
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.json
@@ -0,0 +1,27 @@
+{
+  "description": "collectionOrDatabaseOptions-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "databaseOptions": {
+          "foo": 0
+        }
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.yml b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.yml
new file mode 100644
index 0000000000..e5b92562a2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-additionalProperties.yml
@@ -0,0 +1,17 @@
+description: "collectionOrDatabaseOptions-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      databaseOptions:
+        foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.json b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.json
new file mode 100644
index 0000000000..1b9f4bcbea
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.json
@@ -0,0 +1,27 @@
+{
+  "description": "collectionOrDatabaseOptions-readConcern-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "databaseOptions": {
+          "readConcern": 0
+        }
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.yml b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.yml
new file mode 100644
index 0000000000..671a5b0241
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readConcern-type.yml
@@ -0,0 +1,17 @@
+description: "collectionOrDatabaseOptions-readConcern-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      databaseOptions:
+        readConcern: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.json b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.json
new file mode 100644
index 0000000000..988b594d13
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.json
@@ -0,0 +1,27 @@
+{
+  "description": "collectionOrDatabaseOptions-readPreference-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "databaseOptions": {
+          "readPreference": 0
+        }
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.yml b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.yml
new file mode 100644
index 0000000000..84b328fc46
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-readPreference-type.yml
@@ -0,0 +1,17 @@
+description: "collectionOrDatabaseOptions-readPreference-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      databaseOptions:
+        readPreference: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.json b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.json
new file mode 100644
index 0000000000..bd2157c5cb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.json
@@ -0,0 +1,27 @@
+{
+  "description": "collectionOrDatabaseOptions-writeConcern-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "databaseOptions": {
+          "writeConcern": 0
+        }
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.yml b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.yml
new file mode 100644
index 0000000000..5dc3f8b63c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/collectionOrDatabaseOptions-writeConcern-type.yml
@@ -0,0 +1,17 @@
+description: "collectionOrDatabaseOptions-writeConcern-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      databaseOptions:
+        writeConcern: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/createEntities-items.json b/source/unified-test-format/tests/invalid/createEntities-items.json
new file mode 100644
index 0000000000..8e9d6ff702
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "createEntities-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    0
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/createEntities-items.yml b/source/unified-test-format/tests/invalid/createEntities-items.yml
new file mode 100644
index 0000000000..f0d00e33b2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-items.yml
@@ -0,0 +1,9 @@
+description: "createEntities-items"
+
+schemaVersion: "1.0"
+
+createEntities: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/createEntities-minItems.json b/source/unified-test-format/tests/invalid/createEntities-minItems.json
new file mode 100644
index 0000000000..3654923d28
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-minItems.json
@@ -0,0 +1,11 @@
+{
+  "description": "createEntities-minItems",
+  "schemaVersion": "1.0",
+  "createEntities": [],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/createEntities-minItems.yml b/source/unified-test-format/tests/invalid/createEntities-minItems.yml
new file mode 100644
index 0000000000..11641ea7d8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-minItems.yml
@@ -0,0 +1,9 @@
+description: "createEntities-minItems"
+
+schemaVersion: "1.0"
+
+createEntities: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/createEntities-type.json b/source/unified-test-format/tests/invalid/createEntities-type.json
new file mode 100644
index 0000000000..ce3c382c93
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "createEntities-type",
+  "schemaVersion": "1.0",
+  "createEntities": 0,
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/createEntities-type.yml b/source/unified-test-format/tests/invalid/createEntities-type.yml
new file mode 100644
index 0000000000..c181f31922
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/createEntities-type.yml
@@ -0,0 +1,9 @@
+description: "createEntities-type"
+
+schemaVersion: "1.0"
+
+createEntities: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/description-required.json b/source/unified-test-format/tests/invalid/description-required.json
new file mode 100644
index 0000000000..e4e0d0efdf
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/description-required.json
@@ -0,0 +1,9 @@
+{
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/description-required.yml b/source/unified-test-format/tests/invalid/description-required.yml
new file mode 100644
index 0000000000..5bc6ecff5e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/description-required.yml
@@ -0,0 +1,7 @@
+# description: "description-required"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-additionalProperties.json
new file mode 100644
index 0000000000..38b8898787
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-additionalProperties.json
@@ -0,0 +1,15 @@
+{
+  "description": "entity-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "foo": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-additionalProperties.yml
new file mode 100644
index 0000000000..4978518c5e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-additionalProperties.yml
@@ -0,0 +1,10 @@
+description: "entity-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.json
new file mode 100644
index 0000000000..46f9b4038e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.json
@@ -0,0 +1,31 @@
+{
+  "description": "entity-bucket-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "id": "bucket0",
+        "database": "database0",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.yml
new file mode 100644
index 0000000000..e864aab955
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-additionalProperties.yml
@@ -0,0 +1,19 @@
+description: "entity-bucket-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      id: &bucket0 "bucket0"
+      database: *database0
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.json b/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.json
new file mode 100644
index 0000000000..c3d7423e65
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.json
@@ -0,0 +1,31 @@
+{
+  "description": "entity-bucket-bucketOptions-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "id": "bucket0",
+        "database": "database0",
+        "bucketOptions": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.yml b/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.yml
new file mode 100644
index 0000000000..2d80f5ca3f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-bucketOptions-type.yml
@@ -0,0 +1,19 @@
+description: "entity-bucket-bucketOptions-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      id: &bucket0 "bucket0"
+      database: *database0
+      bucketOptions: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-database-required.json b/source/unified-test-format/tests/invalid/entity-bucket-database-required.json
new file mode 100644
index 0000000000..1fde5a96c9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-database-required.json
@@ -0,0 +1,29 @@
+{
+  "description": "entity-bucket-database-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "id": "bucket0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-database-required.yml b/source/unified-test-format/tests/invalid/entity-bucket-database-required.yml
new file mode 100644
index 0000000000..df7f8d9457
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-database-required.yml
@@ -0,0 +1,17 @@
+description: "entity-bucket-database-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      id: &bucket0 "bucket0"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-database-type.json b/source/unified-test-format/tests/invalid/entity-bucket-database-type.json
new file mode 100644
index 0000000000..798d273fb0
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-database-type.json
@@ -0,0 +1,30 @@
+{
+  "description": "entity-bucket-database-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "id": "bucket0",
+        "database": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-database-type.yml b/source/unified-test-format/tests/invalid/entity-bucket-database-type.yml
new file mode 100644
index 0000000000..e735d16e16
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-database-type.yml
@@ -0,0 +1,18 @@
+description: "entity-bucket-database-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      id: &bucket0 "bucket0"
+      database: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-id-required.json b/source/unified-test-format/tests/invalid/entity-bucket-id-required.json
new file mode 100644
index 0000000000..c547d8ea3c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-id-required.json
@@ -0,0 +1,29 @@
+{
+  "description": "entity-bucket-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "database": "database0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-id-required.yml b/source/unified-test-format/tests/invalid/entity-bucket-id-required.yml
new file mode 100644
index 0000000000..b47435870f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-id-required.yml
@@ -0,0 +1,17 @@
+description: "entity-bucket-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      database: *database0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-id-type.json b/source/unified-test-format/tests/invalid/entity-bucket-id-type.json
new file mode 100644
index 0000000000..f4e10ee630
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-id-type.json
@@ -0,0 +1,30 @@
+{
+  "description": "entity-bucket-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "bucket": {
+        "id": 0,
+        "database": "database0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-bucket-id-type.yml b/source/unified-test-format/tests/invalid/entity-bucket-id-type.yml
new file mode 100644
index 0000000000..33522fea32
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-bucket-id-type.yml
@@ -0,0 +1,18 @@
+description: "entity-bucket-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - bucket:
+      id: 0
+      database: *database0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-client-additionalProperties.json
new file mode 100644
index 0000000000..467e1d6ae1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-additionalProperties.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-client-additionalProperties.yml
new file mode 100644
index 0000000000..b93e51d08a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-additionalProperties.yml
@@ -0,0 +1,12 @@
+description: "entity-client-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-id-required.json b/source/unified-test-format/tests/invalid/entity-client-id-required.json
new file mode 100644
index 0000000000..4be2fbf8e8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-id-required.json
@@ -0,0 +1,15 @@
+{
+  "description": "entity-client-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {}
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-id-required.yml b/source/unified-test-format/tests/invalid/entity-client-id-required.yml
new file mode 100644
index 0000000000..794a025f23
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-id-required.yml
@@ -0,0 +1,10 @@
+description: "entity-client-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client: {}
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-id-type.json b/source/unified-test-format/tests/invalid/entity-client-id-type.json
new file mode 100644
index 0000000000..cdc7cbc0e7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-id-type.json
@@ -0,0 +1,17 @@
+{
+  "description": "entity-client-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-id-type.yml b/source/unified-test-format/tests/invalid/entity-client-id-type.yml
new file mode 100644
index 0000000000..fc872b2b22
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-id-type.yml
@@ -0,0 +1,11 @@
+description: "entity-client-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.json b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.json
new file mode 100644
index 0000000000..1252ac82d7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.json
@@ -0,0 +1,20 @@
+{
+  "description": "entity-client-ignoreCommandMonitoringEvents-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "ignoreCommandMonitoringEvents": [
+          0
+        ]
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.yml b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.yml
new file mode 100644
index 0000000000..8f63e4d7e6
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-items.yml
@@ -0,0 +1,12 @@
+description: "entity-client-ignoreCommandMonitoringEvents-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      ignoreCommandMonitoringEvents: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.json b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.json
new file mode 100644
index 0000000000..e78068a442
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-ignoreCommandMonitoringEvents-minItems",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "ignoreCommandMonitoringEvents": []
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.yml b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.yml
new file mode 100644
index 0000000000..128282c6f3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-minItems.yml
@@ -0,0 +1,12 @@
+description: "entity-client-ignoreCommandMonitoringEvents-minItems"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      ignoreCommandMonitoringEvents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.json b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.json
new file mode 100644
index 0000000000..5ac2b340c5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-ignoreCommandMonitoringEvents-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "ignoreCommandMonitoringEvents": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.yml b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.yml
new file mode 100644
index 0000000000..9fa8bfa323
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-ignoreCommandMonitoringEvents-type.yml
@@ -0,0 +1,12 @@
+description: "entity-client-ignoreCommandMonitoringEvents-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      ignoreCommandMonitoringEvents: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.json b/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.json
new file mode 100644
index 0000000000..c39c94eee2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.json
@@ -0,0 +1,20 @@
+{
+  "description": "entity-client-observeEvents-enum",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          "foo"
+        ]
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.yml b/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.yml
new file mode 100644
index 0000000000..5deaeb6212
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-enum.yml
@@ -0,0 +1,12 @@
+description: "entity-client-observeEvents-enum"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      observeEvents: ["foo"]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.json b/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.json
new file mode 100644
index 0000000000..3aee11e3d5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.json
@@ -0,0 +1,20 @@
+{
+  "description": "entity-client-observeEvents-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          0
+        ]
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.yml b/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.yml
new file mode 100644
index 0000000000..ad73f22699
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-items.yml
@@ -0,0 +1,12 @@
+description: "entity-client-observeEvents-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      observeEvents: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.json b/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.json
new file mode 100644
index 0000000000..e70d90c0a7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-observeEvents-minItems",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": []
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.yml b/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.yml
new file mode 100644
index 0000000000..bd16e78c94
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-minItems.yml
@@ -0,0 +1,12 @@
+description: "entity-client-observeEvents-minItems"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      observeEvents: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.json b/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.json
new file mode 100644
index 0000000000..c144e32369
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-observeEvents-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.yml b/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.yml
new file mode 100644
index 0000000000..b75e97faea
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-observeEvents-type.yml
@@ -0,0 +1,12 @@
+description: "entity-client-observeEvents-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      observeEvents: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.json b/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.json
new file mode 100644
index 0000000000..4252480e98
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-uriOptions-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "uriOptions": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.yml b/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.yml
new file mode 100644
index 0000000000..09bc9f25d3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-uriOptions-type.yml
@@ -0,0 +1,12 @@
+description: "entity-client-uriOptions-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      uriOptions: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.json b/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.json
new file mode 100644
index 0000000000..e429cd71f8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-client-useMultipleMongoses-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.yml b/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.yml
new file mode 100644
index 0000000000..ef5e4baae9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-client-useMultipleMongoses-type.yml
@@ -0,0 +1,12 @@
+description: "entity-client-useMultipleMongoses-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+      useMultipleMongoses: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.json
new file mode 100644
index 0000000000..90ee2b1ca0
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.json
@@ -0,0 +1,32 @@
+{
+  "description": "entity-collection-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.yml
new file mode 100644
index 0000000000..2010de017a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-additionalProperties.yml
@@ -0,0 +1,20 @@
+description: "entity-collection-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: "foo"
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.json b/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.json
new file mode 100644
index 0000000000..2446722e5e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.json
@@ -0,0 +1,30 @@
+{
+  "description": "entity-collection-collectionName-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.yml b/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.yml
new file mode 100644
index 0000000000..97e1616207
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionName-required.yml
@@ -0,0 +1,18 @@
+description: "entity-collection-collectionName-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.json b/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.json
new file mode 100644
index 0000000000..ccad66aac9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.json
@@ -0,0 +1,31 @@
+{
+  "description": "entity-collection-collectionName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.yml b/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.yml
new file mode 100644
index 0000000000..46bcb473f8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionName-type.yml
@@ -0,0 +1,19 @@
+description: "entity-collection-collectionName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.json b/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.json
new file mode 100644
index 0000000000..52220c1cd1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.json
@@ -0,0 +1,32 @@
+{
+  "description": "entity-collection-collectionOptions-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "foo",
+        "collectionOptions": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.yml b/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.yml
new file mode 100644
index 0000000000..58d101981d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-collectionOptions-type.yml
@@ -0,0 +1,20 @@
+description: "entity-collection-collectionOptions-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: *database0
+      collectionName: "foo"
+      collectionOptions: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-database-required.json b/source/unified-test-format/tests/invalid/entity-collection-database-required.json
new file mode 100644
index 0000000000..ba96b43f76
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-database-required.json
@@ -0,0 +1,30 @@
+{
+  "description": "entity-collection-database-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "collectionName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-database-required.yml b/source/unified-test-format/tests/invalid/entity-collection-database-required.yml
new file mode 100644
index 0000000000..6a584cd9b6
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-database-required.yml
@@ -0,0 +1,18 @@
+description: "entity-collection-database-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      collectionName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-database-type.json b/source/unified-test-format/tests/invalid/entity-collection-database-type.json
new file mode 100644
index 0000000000..b87134498d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-database-type.json
@@ -0,0 +1,31 @@
+{
+  "description": "entity-collection-database-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": 0,
+        "collectionName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-database-type.yml b/source/unified-test-format/tests/invalid/entity-collection-database-type.yml
new file mode 100644
index 0000000000..8ed3c743e9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-database-type.yml
@@ -0,0 +1,19 @@
+description: "entity-collection-database-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: &collection0 "collection0"
+      database: 0
+      collectionName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-id-required.json b/source/unified-test-format/tests/invalid/entity-collection-id-required.json
new file mode 100644
index 0000000000..84e5352ead
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-id-required.json
@@ -0,0 +1,30 @@
+{
+  "description": "entity-collection-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "database": "database0",
+        "collectionName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-id-required.yml b/source/unified-test-format/tests/invalid/entity-collection-id-required.yml
new file mode 100644
index 0000000000..83de062263
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-id-required.yml
@@ -0,0 +1,18 @@
+description: "entity-collection-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      database: *database0
+      collectionName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-collection-id-type.json b/source/unified-test-format/tests/invalid/entity-collection-id-type.json
new file mode 100644
index 0000000000..f0821e5250
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-id-type.json
@@ -0,0 +1,31 @@
+{
+  "description": "entity-collection-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    },
+    {
+      "collection": {
+        "id": 0,
+        "database": "database0",
+        "collectionName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-collection-id-type.yml b/source/unified-test-format/tests/invalid/entity-collection-id-type.yml
new file mode 100644
index 0000000000..c7bfa502ee
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-collection-id-type.yml
@@ -0,0 +1,19 @@
+description: "entity-collection-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+  - collection:
+      id: 0
+      database: *database0
+      collectionName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-database-additionalProperties.json
new file mode 100644
index 0000000000..964cd27966
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-additionalProperties.json
@@ -0,0 +1,25 @@
+{
+  "description": "entity-database-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-database-additionalProperties.yml
new file mode 100644
index 0000000000..dcfdc048dc
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-additionalProperties.yml
@@ -0,0 +1,16 @@
+description: "entity-database-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-client-required.json b/source/unified-test-format/tests/invalid/entity-database-client-required.json
new file mode 100644
index 0000000000..54f99cf13e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-client-required.json
@@ -0,0 +1,23 @@
+{
+  "description": "entity-database-client-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-client-required.yml b/source/unified-test-format/tests/invalid/entity-database-client-required.yml
new file mode 100644
index 0000000000..6e271b1859
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-client-required.yml
@@ -0,0 +1,14 @@
+description: "entity-database-client-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-client-type.json b/source/unified-test-format/tests/invalid/entity-database-client-type.json
new file mode 100644
index 0000000000..ff4584c405
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-client-type.json
@@ -0,0 +1,24 @@
+{
+  "description": "entity-database-client-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": 0,
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-client-type.yml b/source/unified-test-format/tests/invalid/entity-database-client-type.yml
new file mode 100644
index 0000000000..fe04610863
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-client-type.yml
@@ -0,0 +1,15 @@
+description: "entity-database-client-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: 0
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseName-required.json b/source/unified-test-format/tests/invalid/entity-database-databaseName-required.json
new file mode 100644
index 0000000000..64cca95c49
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseName-required.json
@@ -0,0 +1,23 @@
+{
+  "description": "entity-database-databaseName-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseName-required.yml b/source/unified-test-format/tests/invalid/entity-database-databaseName-required.yml
new file mode 100644
index 0000000000..cd2c6e77a0
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseName-required.yml
@@ -0,0 +1,14 @@
+description: "entity-database-databaseName-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseName-type.json b/source/unified-test-format/tests/invalid/entity-database-databaseName-type.json
new file mode 100644
index 0000000000..bd01aef781
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseName-type.json
@@ -0,0 +1,24 @@
+{
+  "description": "entity-database-databaseName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseName-type.yml b/source/unified-test-format/tests/invalid/entity-database-databaseName-type.yml
new file mode 100644
index 0000000000..34ec075b64
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseName-type.yml
@@ -0,0 +1,15 @@
+description: "entity-database-databaseName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.json b/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.json
new file mode 100644
index 0000000000..bc22ad3129
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "entity-database-databaseOptions-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo",
+        "databaseOptions": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.yml b/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.yml
new file mode 100644
index 0000000000..77828e5390
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-databaseOptions-type.yml
@@ -0,0 +1,16 @@
+description: "entity-database-databaseOptions-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+      databaseOptions: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-id-required.json b/source/unified-test-format/tests/invalid/entity-database-id-required.json
new file mode 100644
index 0000000000..0b65cf1159
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-id-required.json
@@ -0,0 +1,23 @@
+{
+  "description": "entity-database-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-id-required.yml b/source/unified-test-format/tests/invalid/entity-database-id-required.yml
new file mode 100644
index 0000000000..51e63b4ab1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-id-required.yml
@@ -0,0 +1,14 @@
+description: "entity-database-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      client: *client0
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-database-id-type.json b/source/unified-test-format/tests/invalid/entity-database-id-type.json
new file mode 100644
index 0000000000..98b5789d04
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-id-type.json
@@ -0,0 +1,24 @@
+{
+  "description": "entity-database-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": 0,
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-database-id-type.yml b/source/unified-test-format/tests/invalid/entity-database-id-type.yml
new file mode 100644
index 0000000000..1174c36ca4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-database-id-type.yml
@@ -0,0 +1,15 @@
+description: "entity-database-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - database:
+      id: 0
+      client: *client0
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-maxProperties.json b/source/unified-test-format/tests/invalid/entity-maxProperties.json
new file mode 100644
index 0000000000..f4a6b7c914
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-maxProperties.json
@@ -0,0 +1,22 @@
+{
+  "description": "entity-maxProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      },
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-maxProperties.yml b/source/unified-test-format/tests/invalid/entity-maxProperties.yml
new file mode 100644
index 0000000000..c6f8bcffc5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-maxProperties.yml
@@ -0,0 +1,15 @@
+description: "entity-maxProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+    database:
+      id: &database0 "database0"
+      client: *client0
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-minProperties.json b/source/unified-test-format/tests/invalid/entity-minProperties.json
new file mode 100644
index 0000000000..d89949ce30
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-minProperties.json
@@ -0,0 +1,13 @@
+{
+  "description": "entity-minProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {}
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-minProperties.yml b/source/unified-test-format/tests/invalid/entity-minProperties.yml
new file mode 100644
index 0000000000..d758bd5745
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-minProperties.yml
@@ -0,0 +1,10 @@
+description: "entity-minProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - {}
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-session-additionalProperties.json
new file mode 100644
index 0000000000..ab4cd2014f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-additionalProperties.json
@@ -0,0 +1,24 @@
+{
+  "description": "entity-session-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-session-additionalProperties.yml
new file mode 100644
index 0000000000..1bb2233043
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-additionalProperties.yml
@@ -0,0 +1,15 @@
+description: "entity-session-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      id: &session0 "session0"
+      client: *client0
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-client-required.json b/source/unified-test-format/tests/invalid/entity-session-client-required.json
new file mode 100644
index 0000000000..8c9ed72e99
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-client-required.json
@@ -0,0 +1,22 @@
+{
+  "description": "entity-session-client-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": "session0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-client-required.yml b/source/unified-test-format/tests/invalid/entity-session-client-required.yml
new file mode 100644
index 0000000000..3c1fe4e3c0
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-client-required.yml
@@ -0,0 +1,13 @@
+description: "entity-session-client-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      id: &session0 "session0"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-client-type.json b/source/unified-test-format/tests/invalid/entity-session-client-type.json
new file mode 100644
index 0000000000..b5ccc3f60f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-client-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "entity-session-client-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-client-type.yml b/source/unified-test-format/tests/invalid/entity-session-client-type.yml
new file mode 100644
index 0000000000..60353c08db
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-client-type.yml
@@ -0,0 +1,14 @@
+description: "entity-session-client-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      id: &session0 "session0"
+      client: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-id-required.json b/source/unified-test-format/tests/invalid/entity-session-id-required.json
new file mode 100644
index 0000000000..3e5d5c5439
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-id-required.json
@@ -0,0 +1,22 @@
+{
+  "description": "entity-session-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "client": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-id-required.yml b/source/unified-test-format/tests/invalid/entity-session-id-required.yml
new file mode 100644
index 0000000000..2aa4269d16
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-id-required.yml
@@ -0,0 +1,13 @@
+description: "entity-session-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      client: *client0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-id-type.json b/source/unified-test-format/tests/invalid/entity-session-id-type.json
new file mode 100644
index 0000000000..dcd46e5be7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-id-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "entity-session-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": 0,
+        "client": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-id-type.yml b/source/unified-test-format/tests/invalid/entity-session-id-type.yml
new file mode 100644
index 0000000000..058dcdb1b7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-id-type.yml
@@ -0,0 +1,14 @@
+description: "entity-session-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      id: 0
+      client: *client0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.json b/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.json
new file mode 100644
index 0000000000..0ee15891eb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.json
@@ -0,0 +1,24 @@
+{
+  "description": "entity-session-sessionOptions-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0",
+        "sessionOptions": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.yml b/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.yml
new file mode 100644
index 0000000000..2d651f690b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-session-sessionOptions-type.yml
@@ -0,0 +1,15 @@
+description: "entity-session-sessionOptions-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+  - session:
+      id: &session0 "session0"
+      client: *client0
+      sessionOptions: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.json b/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.json
new file mode 100644
index 0000000000..c8e76e9985
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.json
@@ -0,0 +1,19 @@
+{
+  "description": "entity-stream-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "id": "stream0",
+        "hexBytes": "FF",
+        "foo": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.yml b/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.yml
new file mode 100644
index 0000000000..e2f4f8e93d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-additionalProperties.yml
@@ -0,0 +1,13 @@
+description: "entity-stream-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      id: &stream0 "stream0"
+      hexBytes: "FF"
+      foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.json b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.json
new file mode 100644
index 0000000000..7381893b55
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-stream-hexBytes-pattern",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "id": "stream0",
+        "hexBytes": "FFF"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.yml b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.yml
new file mode 100644
index 0000000000..3e1aa8e45d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-pattern.yml
@@ -0,0 +1,12 @@
+description: "entity-stream-hexBytes-pattern"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      id: &stream0 "stream0"
+      hexBytes: "FFF"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.json b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.json
new file mode 100644
index 0000000000..cc3bf09b20
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.json
@@ -0,0 +1,17 @@
+{
+  "description": "entity-stream-hexBytes-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "id": "stream0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.yml b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.yml
new file mode 100644
index 0000000000..b1a4b98561
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-required.yml
@@ -0,0 +1,11 @@
+description: "entity-stream-hexBytes-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      id: &stream0 "stream0"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.json b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.json
new file mode 100644
index 0000000000..e6e2299eac
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-stream-hexBytes-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "id": "stream0",
+        "hexBytes": 0
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.yml b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.yml
new file mode 100644
index 0000000000..79b8188c5b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-hexBytes-type.yml
@@ -0,0 +1,12 @@
+description: "entity-stream-hexBytes-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      id: &stream0 "stream0"
+      hexBytes: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-id-required.json b/source/unified-test-format/tests/invalid/entity-stream-id-required.json
new file mode 100644
index 0000000000..ff814d4e9c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-id-required.json
@@ -0,0 +1,17 @@
+{
+  "description": "entity-stream-id-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "hexBytes": "FF"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-id-required.yml b/source/unified-test-format/tests/invalid/entity-stream-id-required.yml
new file mode 100644
index 0000000000..0ca388aade
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-id-required.yml
@@ -0,0 +1,11 @@
+description: "entity-stream-id-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      hexBytes: "FF"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/entity-stream-id-type.json b/source/unified-test-format/tests/invalid/entity-stream-id-type.json
new file mode 100644
index 0000000000..5fc654d97e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-id-type.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-stream-id-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "stream": {
+        "id": 0,
+        "hexBytes": "FF"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/entity-stream-id-type.yml b/source/unified-test-format/tests/invalid/entity-stream-id-type.yml
new file mode 100644
index 0000000000..d7b17952cb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/entity-stream-id-type.yml
@@ -0,0 +1,12 @@
+description: "entity-stream-id-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - stream:
+      id: 0
+      hexBytes: "FF"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/expectedError-additionalProperties.json b/source/unified-test-format/tests/invalid/expectedError-additionalProperties.json
new file mode 100644
index 0000000000..3a79df8e34
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-additionalProperties.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "foo": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-additionalProperties.yml b/source/unified-test-format/tests/invalid/expectedError-additionalProperties.yml
new file mode 100644
index 0000000000..6146367962
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-additionalProperties.yml
@@ -0,0 +1,15 @@
+description: "expectedError-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          foo: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorCode-type.json b/source/unified-test-format/tests/invalid/expectedError-errorCode-type.json
new file mode 100644
index 0000000000..b6b6f5d05a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorCode-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorCode-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorCode": "foo"
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorCode-type.yml b/source/unified-test-format/tests/invalid/expectedError-errorCode-type.yml
new file mode 100644
index 0000000000..2110e9c6ad
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorCode-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorCode-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorCode: "foo"
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.json b/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.json
new file mode 100644
index 0000000000..3ac5e43045
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorCodeName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorCodeName": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.yml b/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.yml
new file mode 100644
index 0000000000..c35ec3ed4a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorCodeName-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorCodeName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorCodeName: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorContains-type.json b/source/unified-test-format/tests/invalid/expectedError-errorContains-type.json
new file mode 100644
index 0000000000..847a987dff
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorContains-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorContains-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorContains": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorContains-type.yml b/source/unified-test-format/tests/invalid/expectedError-errorContains-type.yml
new file mode 100644
index 0000000000..f4989b61e3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorContains-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorContains-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorContains: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.json
new file mode 100644
index 0000000000..4eab56ad18
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.json
@@ -0,0 +1,27 @@
+{
+  "description": "expectedError-errorLabelsContain-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsContain": [
+              0
+            ]
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.yml
new file mode 100644
index 0000000000..4382fa645a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-items.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsContain-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsContain: [0]
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.json
new file mode 100644
index 0000000000..48162110aa
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorLabelsContain-minItems",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsContain": []
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.yml
new file mode 100644
index 0000000000..ebd650e11a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-minItems.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsContain-minItems"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsContain: []
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.json
new file mode 100644
index 0000000000..a0aba918b5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorLabelsContain-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsContain": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.yml
new file mode 100644
index 0000000000..537cfb9cfe
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsContain-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsContain-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsContain: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.json
new file mode 100644
index 0000000000..6c94d07135
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.json
@@ -0,0 +1,27 @@
+{
+  "description": "expectedError-errorLabelsOmit-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsOmit": [
+              0
+            ]
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.yml
new file mode 100644
index 0000000000..d80711ef0f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-items.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsOmit-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsOmit: [0]
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.json
new file mode 100644
index 0000000000..88c6582028
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorLabelsOmit-minItems",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsOmit": []
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.yml
new file mode 100644
index 0000000000..205162cf67
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-minItems.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsOmit-minItems"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsOmit: []
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.json b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.json
new file mode 100644
index 0000000000..5f57114fea
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-errorLabelsOmit-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "errorLabelsOmit": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.yml b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.yml
new file mode 100644
index 0000000000..6c1947b043
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-errorLabelsOmit-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-errorLabelsOmit-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          errorLabelsOmit: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-isClientError-type.json b/source/unified-test-format/tests/invalid/expectedError-isClientError-type.json
new file mode 100644
index 0000000000..bfcc06679b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isClientError-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-isClientError-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "isClientError": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-isClientError-type.yml b/source/unified-test-format/tests/invalid/expectedError-isClientError-type.yml
new file mode 100644
index 0000000000..8b8afc1061
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isClientError-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-isClientError-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          isClientError: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-isError-const.json b/source/unified-test-format/tests/invalid/expectedError-isError-const.json
new file mode 100644
index 0000000000..6a398bbf22
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isError-const.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-isError-const",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "isError": false
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-isError-const.yml b/source/unified-test-format/tests/invalid/expectedError-isError-const.yml
new file mode 100644
index 0000000000..347ae2965a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isError-const.yml
@@ -0,0 +1,15 @@
+description: "expectedError-isError-const"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          isError: false
diff --git a/source/unified-test-format/tests/invalid/expectedError-isError-type.json b/source/unified-test-format/tests/invalid/expectedError-isError-type.json
new file mode 100644
index 0000000000..354aff31f4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isError-type.json
@@ -0,0 +1,25 @@
+{
+  "description": "expectedError-isError-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "isError": 0
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-isError-type.yml b/source/unified-test-format/tests/invalid/expectedError-isError-type.yml
new file mode 100644
index 0000000000..3e53f4af90
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-isError-type.yml
@@ -0,0 +1,15 @@
+description: "expectedError-isError-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          isError: 0
diff --git a/source/unified-test-format/tests/invalid/expectedError-minProperties.json b/source/unified-test-format/tests/invalid/expectedError-minProperties.json
new file mode 100644
index 0000000000..10e0b89ab7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-minProperties.json
@@ -0,0 +1,23 @@
+{
+  "description": "expectedError-minProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {}
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedError-minProperties.yml b/source/unified-test-format/tests/invalid/expectedError-minProperties.yml
new file mode 100644
index 0000000000..5292d85008
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedError-minProperties.yml
@@ -0,0 +1,14 @@
+description: "expectedError-minProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError: {}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.json b/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.json
new file mode 100644
index 0000000000..2c4f7d27e7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.json
@@ -0,0 +1,32 @@
+{
+  "description": "expectedEvent-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "foo": 0
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.yml b/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.yml
new file mode 100644
index 0000000000..c2c1cb5a7c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-additionalProperties.yml
@@ -0,0 +1,17 @@
+description: "expectedEvent-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - foo: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.json
new file mode 100644
index 0000000000..ea6078faae
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandFailedEvent-commandName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandFailedEvent": {
+                    "commandName": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.yml
new file mode 100644
index 0000000000..57504b78f8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandFailedEvent-commandName-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandFailedEvent-commandName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandFailedEvent:
+                  commandName: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.json b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.json
new file mode 100644
index 0000000000..ee6eb50658
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandStartedEvent-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandStartedEvent": {
+                    "foo": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.yml
new file mode 100644
index 0000000000..6ea724ddfb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-additionalProperties.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandStartedEvent-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandStartedEvent:
+                  foo: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.json
new file mode 100644
index 0000000000..4c9483caf3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandStartedEvent-command-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandStartedEvent": {
+                    "command": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.yml
new file mode 100644
index 0000000000..91ba129869
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-command-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandStartedEvent-command-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandStartedEvent:
+                  command: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.json
new file mode 100644
index 0000000000..a5a66096a0
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandStartedEvent-commandName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandStartedEvent": {
+                    "commandName": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.yml
new file mode 100644
index 0000000000..07c968cdd4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-commandName-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandStartedEvent-commandName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandStartedEvent:
+                  commandName: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.json
new file mode 100644
index 0000000000..dc040ec108
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandStartedEvent-databaseName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandStartedEvent": {
+                    "databaseName": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.yml
new file mode 100644
index 0000000000..355d90d6f7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandStartedEvent-databaseName-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandStartedEvent-databaseName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandStartedEvent:
+                  databaseName: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.json
new file mode 100644
index 0000000000..4a20e906b9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandSucceededEvent-commandName-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandSucceededEvent": {
+                    "commandName": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.yml
new file mode 100644
index 0000000000..740b377fa2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-commandName-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandSucceededEvent-commandName-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandSucceededEvent:
+                  commandName: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.json b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.json
new file mode 100644
index 0000000000..5464542751
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.json
@@ -0,0 +1,34 @@
+{
+  "description": "expectedEvent-commandSucceededEvent-reply-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandSucceededEvent": {
+                    "reply": 0
+                  }
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.yml b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.yml
new file mode 100644
index 0000000000..5a4b35e272
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-commandSucceededEvent-reply-type.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-commandSucceededEvent-reply-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandSucceededEvent:
+                  reply: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.json b/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.json
new file mode 100644
index 0000000000..f01441946f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.json
@@ -0,0 +1,33 @@
+{
+  "description": "expectedEvent-maxProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {
+                  "commandStartedEvent": {},
+                  "commandSucceededEvent": {}
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.yml b/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.yml
new file mode 100644
index 0000000000..d349133ea1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-maxProperties.yml
@@ -0,0 +1,18 @@
+description: "expectedEvent-maxProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - commandStartedEvent: {}
+                commandSucceededEvent: {}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-minProperties.json b/source/unified-test-format/tests/invalid/expectedEvent-minProperties.json
new file mode 100644
index 0000000000..ebcc494894
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-minProperties.json
@@ -0,0 +1,30 @@
+{
+  "description": "expectedEvent-minProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                {}
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEvent-minProperties.yml b/source/unified-test-format/tests/invalid/expectedEvent-minProperties.yml
new file mode 100644
index 0000000000..88de63a898
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEvent-minProperties.yml
@@ -0,0 +1,17 @@
+description: "expectedEvent-minProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events:
+              - {}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.json
new file mode 100644
index 0000000000..6ecf5931fb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.json
@@ -0,0 +1,29 @@
+{
+  "description": "expectedEventsForClient-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [],
+              "foo": 0
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.yml
new file mode 100644
index 0000000000..a15835d1ca
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-additionalProperties.yml
@@ -0,0 +1,17 @@
+description: "expectedEventsForClient-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events: []
+            foo: 0
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.json
new file mode 100644
index 0000000000..b879db8598
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.json
@@ -0,0 +1,27 @@
+{
+  "description": "expectedEventsForClient-client-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "events": []
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.yml
new file mode 100644
index 0000000000..57db7b07e2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-required.yml
@@ -0,0 +1,15 @@
+description: "expectedEventsForClient-client-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - events: []
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.json
new file mode 100644
index 0000000000..4ee5427df1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.json
@@ -0,0 +1,28 @@
+{
+  "description": "expectedEventsForClient-client-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": 0,
+              "events": []
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.yml
new file mode 100644
index 0000000000..015fd7849b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-client-type.yml
@@ -0,0 +1,16 @@
+description: "expectedEventsForClient-client-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: 0
+            events: []
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.json
new file mode 100644
index 0000000000..ee8ce4a403
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.json
@@ -0,0 +1,30 @@
+{
+  "description": "expectedEventsForClient-events-items",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": [
+                0
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.yml
new file mode 100644
index 0000000000..e5a6f4606b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-items.yml
@@ -0,0 +1,16 @@
+description: "expectedEventsForClient-events-items"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events: [0]
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.json
new file mode 100644
index 0000000000..7f1bc6fb53
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.json
@@ -0,0 +1,27 @@
+{
+  "description": "expectedEventsForClient-events-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0"
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.yml
new file mode 100644
index 0000000000..dd14eb2b8e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-required.yml
@@ -0,0 +1,15 @@
+description: "expectedEventsForClient-events-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.json b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.json
new file mode 100644
index 0000000000..f171fc2b93
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.json
@@ -0,0 +1,28 @@
+{
+  "description": "expectedEventsForClient-events-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": [
+            {
+              "client": "client0",
+              "events": 0
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.yml b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.yml
new file mode 100644
index 0000000000..b51730f4ff
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/expectedEventsForClient-events-type.yml
@@ -0,0 +1,16 @@
+description: "expectedEventsForClient-events-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents:
+          - client: *client0
+            events: 0
diff --git a/source/unified-test-format/tests/invalid/initialData-items.json b/source/unified-test-format/tests/invalid/initialData-items.json
new file mode 100644
index 0000000000..9c27d554f9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "initialData-items",
+  "schemaVersion": "1.0",
+  "initialData": [
+    0
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/initialData-items.yml b/source/unified-test-format/tests/invalid/initialData-items.yml
new file mode 100644
index 0000000000..87fa3e562b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-items.yml
@@ -0,0 +1,9 @@
+description: "initialData-items"
+
+schemaVersion: "1.0"
+
+initialData: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/initialData-minItems.json b/source/unified-test-format/tests/invalid/initialData-minItems.json
new file mode 100644
index 0000000000..984100a2be
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-minItems.json
@@ -0,0 +1,11 @@
+{
+  "description": "initialData-minItems",
+  "schemaVersion": "1.0",
+  "initialData": [],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/initialData-minItems.yml b/source/unified-test-format/tests/invalid/initialData-minItems.yml
new file mode 100644
index 0000000000..dc1afde97f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-minItems.yml
@@ -0,0 +1,9 @@
+description: "initialData-minItems"
+
+schemaVersion: "1.0"
+
+initialData: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/initialData-type.json b/source/unified-test-format/tests/invalid/initialData-type.json
new file mode 100644
index 0000000000..c33585e03a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "initialData-type",
+  "schemaVersion": "1.0",
+  "initialData": 0,
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/initialData-type.yml b/source/unified-test-format/tests/invalid/initialData-type.yml
new file mode 100644
index 0000000000..946c0e4364
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/initialData-type.yml
@@ -0,0 +1,9 @@
+description: "initialData-type"
+
+schemaVersion: "1.0"
+
+initialData: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/operation-additionalProperties.json b/source/unified-test-format/tests/invalid/operation-additionalProperties.json
new file mode 100644
index 0000000000..8f2f1434ec
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-additionalProperties.json
@@ -0,0 +1,23 @@
+{
+  "description": "operation-additionalProperties",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "foo": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-additionalProperties.yml b/source/unified-test-format/tests/invalid/operation-additionalProperties.yml
new file mode 100644
index 0000000000..d5dbef8e8f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-additionalProperties.yml
@@ -0,0 +1,14 @@
+description: "operation-additionalProperties"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        foo: 0
diff --git a/source/unified-test-format/tests/invalid/operation-arguments-type.json b/source/unified-test-format/tests/invalid/operation-arguments-type.json
new file mode 100644
index 0000000000..a22f3921c3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-arguments-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "operation-arguments-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "arguments": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-arguments-type.yml b/source/unified-test-format/tests/invalid/operation-arguments-type.yml
new file mode 100644
index 0000000000..1564f21601
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-arguments-type.yml
@@ -0,0 +1,14 @@
+description: "operation-arguments-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        arguments: 0
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.json b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.json
new file mode 100644
index 0000000000..bc15fbac76
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.json
@@ -0,0 +1,26 @@
+{
+  "description": "operation-expectError-conflicts_with_expectResult",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "isError": true
+          },
+          "expectResult": {}
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.yml b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.yml
new file mode 100644
index 0000000000..aa9430fdb1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_expectResult.yml
@@ -0,0 +1,16 @@
+description: "operation-expectError-conflicts_with_expectResult"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          isError: true
+        expectResult: {}
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.json b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.json
new file mode 100644
index 0000000000..dead4a3b9d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.json
@@ -0,0 +1,26 @@
+{
+  "description": "operation-expectError-conflicts_with_saveResultAsEntity",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": {
+            "isError": true
+          },
+          "saveResultAsEntity": "foo"
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.yml b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.yml
new file mode 100644
index 0000000000..6c369598fe
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-conflicts_with_saveResultAsEntity.yml
@@ -0,0 +1,16 @@
+description: "operation-expectError-conflicts_with_saveResultAsEntity"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError:
+          isError: true
+        saveResultAsEntity: "foo"
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-type.json b/source/unified-test-format/tests/invalid/operation-expectError-type.json
new file mode 100644
index 0000000000..b224ba3535
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "operation-expectError-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectError": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-expectError-type.yml b/source/unified-test-format/tests/invalid/operation-expectError-type.yml
new file mode 100644
index 0000000000..55588d4359
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectError-type.yml
@@ -0,0 +1,14 @@
+description: "operation-expectError-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectError: 0
diff --git a/source/unified-test-format/tests/invalid/operation-expectEvents-type.json b/source/unified-test-format/tests/invalid/operation-expectEvents-type.json
new file mode 100644
index 0000000000..ecd4c011a9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectEvents-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "operation-expectEvents-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "expectEvents": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-expectEvents-type.yml b/source/unified-test-format/tests/invalid/operation-expectEvents-type.yml
new file mode 100644
index 0000000000..2c9936ed28
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-expectEvents-type.yml
@@ -0,0 +1,14 @@
+description: "operation-expectEvents-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        expectEvents: 0
diff --git a/source/unified-test-format/tests/invalid/operation-name-required.json b/source/unified-test-format/tests/invalid/operation-name-required.json
new file mode 100644
index 0000000000..42fcb3a308
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-name-required.json
@@ -0,0 +1,21 @@
+{
+  "description": "operation-name-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "object": "client0"
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-name-required.yml b/source/unified-test-format/tests/invalid/operation-name-required.yml
new file mode 100644
index 0000000000..253cb579b9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-name-required.yml
@@ -0,0 +1,12 @@
+description: "operation-name-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - object: *client0
diff --git a/source/unified-test-format/tests/invalid/operation-name-type.json b/source/unified-test-format/tests/invalid/operation-name-type.json
new file mode 100644
index 0000000000..2f91da078a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-name-type.json
@@ -0,0 +1,22 @@
+{
+  "description": "operation-name-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": 0,
+          "object": "client0"
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-name-type.yml b/source/unified-test-format/tests/invalid/operation-name-type.yml
new file mode 100644
index 0000000000..f9323050b5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-name-type.yml
@@ -0,0 +1,13 @@
+description: "operation-name-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: 0
+        object: *client0
diff --git a/source/unified-test-format/tests/invalid/operation-object-required.json b/source/unified-test-format/tests/invalid/operation-object-required.json
new file mode 100644
index 0000000000..c0410ce3fd
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-object-required.json
@@ -0,0 +1,21 @@
+{
+  "description": "operation-object-required",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo"
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-object-required.yml b/source/unified-test-format/tests/invalid/operation-object-required.yml
new file mode 100644
index 0000000000..eec6101bbe
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-object-required.yml
@@ -0,0 +1,12 @@
+description: "operation-object-required"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
diff --git a/source/unified-test-format/tests/invalid/operation-object-type.json b/source/unified-test-format/tests/invalid/operation-object-type.json
new file mode 100644
index 0000000000..edb0a0b51a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-object-type.json
@@ -0,0 +1,22 @@
+{
+  "description": "operation-object-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-object-type.yml b/source/unified-test-format/tests/invalid/operation-object-type.yml
new file mode 100644
index 0000000000..fb8e10267b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-object-type.yml
@@ -0,0 +1,13 @@
+description: "operation-object-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: 0
diff --git a/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.json b/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.json
new file mode 100644
index 0000000000..65ead94c7a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.json
@@ -0,0 +1,23 @@
+{
+  "description": "operation-saveResultAsEntity-type",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        {
+          "name": "foo",
+          "object": "client0",
+          "saveResultAsEntity": 0
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.yml b/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.yml
new file mode 100644
index 0000000000..7d20938f32
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/operation-saveResultAsEntity-type.yml
@@ -0,0 +1,14 @@
+description: "operation-saveResultAsEntity-type"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 "client0"
+
+tests:
+  - description: "foo"
+    operations:
+      - name: "foo"
+        object: *client0
+        saveResultAsEntity: 0
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.json b/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.json
new file mode 100644
index 0000000000..79fa687e45
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.json
@@ -0,0 +1,16 @@
+{
+  "description": "runOnRequirement-additionalProperties",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.0",
+      "foo": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.yml b/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.yml
new file mode 100644
index 0000000000..044b803d29
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-additionalProperties.yml
@@ -0,0 +1,11 @@
+description: "runOnRequirement-additionalProperties"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "4.0"
+    foo: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.json b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.json
new file mode 100644
index 0000000000..78766eb925
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-maxServerVersion-pattern",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "maxServerVersion": "1.2.3.4"
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.yml b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.yml
new file mode 100644
index 0000000000..ce5af27df5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-pattern.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-maxServerVersion-pattern"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - maxServerVersion: "1.2.3.4"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.json b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.json
new file mode 100644
index 0000000000..ffc9118ba2
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-maxServerVersion-type",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "maxServerVersion": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.yml b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.yml
new file mode 100644
index 0000000000..a63df28232
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-maxServerVersion-type.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-maxServerVersion-type"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - maxServerVersion: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.json b/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.json
new file mode 100644
index 0000000000..c2bfed3be7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.json
@@ -0,0 +1,13 @@
+{
+  "description": "runOnRequirement-minProperties",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {}
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.yml b/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.yml
new file mode 100644
index 0000000000..e8b91fd4f5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minProperties.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-minProperties"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - {}
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.json b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.json
new file mode 100644
index 0000000000..19abc1755f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-minServerVersion-pattern",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "1.2.3.4"
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.yml b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.yml
new file mode 100644
index 0000000000..69d4986665
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-pattern.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-minServerVersion-pattern"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "1.2.3.4"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.json b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.json
new file mode 100644
index 0000000000..688d1c67ee
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-minServerVersion-type",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.yml b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.yml
new file mode 100644
index 0000000000..e2727c5800
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-minServerVersion-type.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-minServerVersion-type"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.json b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.json
new file mode 100644
index 0000000000..f62e5040d4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.json
@@ -0,0 +1,17 @@
+{
+  "description": "runOnRequirement-topologies-enum",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "topologies": [
+        "foo"
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.yml b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.yml
new file mode 100644
index 0000000000..924a67515d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-enum.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-topologies-enum"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - topologies: ["foo"]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.json b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.json
new file mode 100644
index 0000000000..a205b3293d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.json
@@ -0,0 +1,17 @@
+{
+  "description": "runOnRequirement-topologies-items",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "topologies": [
+        0
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.yml b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.yml
new file mode 100644
index 0000000000..7b2265fb26
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-items.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-topologies-items"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - topologies: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.json b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.json
new file mode 100644
index 0000000000..16f29b3f4b
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-topologies-minItems",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "topologies": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.yml b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.yml
new file mode 100644
index 0000000000..3e6d11ab8f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-minItems.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-topologies-minItems"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - topologies: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.json b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.json
new file mode 100644
index 0000000000..f6d147cd6f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.json
@@ -0,0 +1,15 @@
+{
+  "description": "runOnRequirement-topologies-type",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "topologies": 0
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.yml b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.yml
new file mode 100644
index 0000000000..5a1652d8d9
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirement-topologies-type.yml
@@ -0,0 +1,10 @@
+description: "runOnRequirement-topologies-type"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - topologies: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-items.json b/source/unified-test-format/tests/invalid/runOnRequirements-items.json
new file mode 100644
index 0000000000..40ec84a3f3
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "runOnRequirements-items",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    0
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-items.yml b/source/unified-test-format/tests/invalid/runOnRequirements-items.yml
new file mode 100644
index 0000000000..a86bbb1318
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-items.yml
@@ -0,0 +1,9 @@
+description: "runOnRequirements-items"
+
+schemaVersion: "1.0"
+
+runOnRequirements: [0]
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-minItems.json b/source/unified-test-format/tests/invalid/runOnRequirements-minItems.json
new file mode 100644
index 0000000000..4ca9f99b5d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-minItems.json
@@ -0,0 +1,11 @@
+{
+  "description": "runOnRequirements-minItems",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-minItems.yml b/source/unified-test-format/tests/invalid/runOnRequirements-minItems.yml
new file mode 100644
index 0000000000..034786a220
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-minItems.yml
@@ -0,0 +1,9 @@
+description: "runOnRequirements-minItems"
+
+schemaVersion: "1.0"
+
+runOnRequirements: []
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-type.json b/source/unified-test-format/tests/invalid/runOnRequirements-type.json
new file mode 100644
index 0000000000..98b859f3ea
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "runOnRequirements-type",
+  "schemaVersion": "1.0",
+  "runOnRequirements": 0,
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/runOnRequirements-type.yml b/source/unified-test-format/tests/invalid/runOnRequirements-type.yml
new file mode 100644
index 0000000000..42afc21ced
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/runOnRequirements-type.yml
@@ -0,0 +1,9 @@
+description: "runOnRequirements-type"
+
+schemaVersion: "1.0"
+
+runOnRequirements: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-pattern.json b/source/unified-test-format/tests/invalid/schemaVersion-pattern.json
new file mode 100644
index 0000000000..bcb8980516
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-pattern.json
@@ -0,0 +1,10 @@
+{
+  "description": "schemaVersion-pattern",
+  "schemaVersion": "1.2.3.4",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-pattern.yml b/source/unified-test-format/tests/invalid/schemaVersion-pattern.yml
new file mode 100644
index 0000000000..3d36ee64b5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-pattern.yml
@@ -0,0 +1,7 @@
+description: "schemaVersion-pattern"
+
+schemaVersion: "1.2.3.4"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-required.json b/source/unified-test-format/tests/invalid/schemaVersion-required.json
new file mode 100644
index 0000000000..7388ff0bf1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-required.json
@@ -0,0 +1,9 @@
+{
+  "description": "schemaVersion-required",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-required.yml b/source/unified-test-format/tests/invalid/schemaVersion-required.yml
new file mode 100644
index 0000000000..14a13872d8
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-required.yml
@@ -0,0 +1,5 @@
+description: "schemaVersion-required"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-type.json b/source/unified-test-format/tests/invalid/schemaVersion-type.json
new file mode 100644
index 0000000000..646473a209
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-type.json
@@ -0,0 +1,10 @@
+{
+  "description": "schemaVersion-type",
+  "schemaVersion": 0,
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/schemaVersion-type.yml b/source/unified-test-format/tests/invalid/schemaVersion-type.yml
new file mode 100644
index 0000000000..9dfeed1e78
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/schemaVersion-type.yml
@@ -0,0 +1,7 @@
+description: "schemaVersion-type"
+
+schemaVersion: 0
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/invalid/test-additionalProperties.json b/source/unified-test-format/tests/invalid/test-additionalProperties.json
new file mode 100644
index 0000000000..a699319c30
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-additionalProperties.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-additionalProperties",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "foo": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-additionalProperties.yml b/source/unified-test-format/tests/invalid/test-additionalProperties.yml
new file mode 100644
index 0000000000..65a2e2aa64
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-additionalProperties.yml
@@ -0,0 +1,8 @@
+description: "test-additionalProperties"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    foo: 0
diff --git a/source/unified-test-format/tests/invalid/test-description-required.json b/source/unified-test-format/tests/invalid/test-description-required.json
new file mode 100644
index 0000000000..8bf23014d4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-description-required.json
@@ -0,0 +1,9 @@
+{
+  "description": "test-description-required",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "operation": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-description-required.yml b/source/unified-test-format/tests/invalid/test-description-required.yml
new file mode 100644
index 0000000000..d1c725b69a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-description-required.yml
@@ -0,0 +1,6 @@
+description: "test-description-required"
+
+schemaVersion: "1.0"
+
+tests:
+  - operation: []
diff --git a/source/unified-test-format/tests/invalid/test-description-type.json b/source/unified-test-format/tests/invalid/test-description-type.json
new file mode 100644
index 0000000000..bba3690449
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-description-type.json
@@ -0,0 +1,10 @@
+{
+  "description": "test-description-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": 0,
+      "operation": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-description-type.yml b/source/unified-test-format/tests/invalid/test-description-type.yml
new file mode 100644
index 0000000000..891db9bbc1
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-description-type.yml
@@ -0,0 +1,7 @@
+description: "test-description-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: 0
+    operation: []
diff --git a/source/unified-test-format/tests/invalid/test-expectEvents-items.json b/source/unified-test-format/tests/invalid/test-expectEvents-items.json
new file mode 100644
index 0000000000..394f74746c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-expectEvents-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "test-expectEvents-items",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "expectEvents": [
+        0
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-expectEvents-items.yml b/source/unified-test-format/tests/invalid/test-expectEvents-items.yml
new file mode 100644
index 0000000000..1a889b1b4f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-expectEvents-items.yml
@@ -0,0 +1,8 @@
+description: "test-expectEvents-items"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    expectEvents: [0]
diff --git a/source/unified-test-format/tests/invalid/test-expectEvents-type.json b/source/unified-test-format/tests/invalid/test-expectEvents-type.json
new file mode 100644
index 0000000000..1569f0a0d7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-expectEvents-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-expectEvents-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "expectEvents": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-expectEvents-type.yml b/source/unified-test-format/tests/invalid/test-expectEvents-type.yml
new file mode 100644
index 0000000000..0a1e9d97d5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-expectEvents-type.yml
@@ -0,0 +1,8 @@
+description: "test-expectEvents-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    expectEvents: 0
diff --git a/source/unified-test-format/tests/invalid/test-operations-items.json b/source/unified-test-format/tests/invalid/test-operations-items.json
new file mode 100644
index 0000000000..00af8e7453
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-items.json
@@ -0,0 +1,12 @@
+{
+  "description": "test-operations-items",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [
+        0
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-operations-items.yml b/source/unified-test-format/tests/invalid/test-operations-items.yml
new file mode 100644
index 0000000000..6bb097fa3c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-items.yml
@@ -0,0 +1,7 @@
+description: "test-operations-items"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: [0]
diff --git a/source/unified-test-format/tests/invalid/test-operations-required.json b/source/unified-test-format/tests/invalid/test-operations-required.json
new file mode 100644
index 0000000000..67c6f83044
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-required.json
@@ -0,0 +1,9 @@
+{
+  "description": "test-operations-required",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo"
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-operations-required.yml b/source/unified-test-format/tests/invalid/test-operations-required.yml
new file mode 100644
index 0000000000..80af1a900a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-required.yml
@@ -0,0 +1,6 @@
+description: "test-operations-required"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
diff --git a/source/unified-test-format/tests/invalid/test-operations-type.json b/source/unified-test-format/tests/invalid/test-operations-type.json
new file mode 100644
index 0000000000..1e8b5b2496
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-type.json
@@ -0,0 +1,10 @@
+{
+  "description": "test-operations-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-operations-type.yml b/source/unified-test-format/tests/invalid/test-operations-type.yml
new file mode 100644
index 0000000000..713c7ff0ec
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-operations-type.yml
@@ -0,0 +1,7 @@
+description: "test-operations-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: 0
diff --git a/source/unified-test-format/tests/invalid/test-outcome-items.json b/source/unified-test-format/tests/invalid/test-outcome-items.json
new file mode 100644
index 0000000000..cf6bb54f87
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "test-outcome-items",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "outcome": [
+        0
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-outcome-items.yml b/source/unified-test-format/tests/invalid/test-outcome-items.yml
new file mode 100644
index 0000000000..bd5565e4fb
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-items.yml
@@ -0,0 +1,8 @@
+description: "test-outcome-items"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    outcome: [0]
diff --git a/source/unified-test-format/tests/invalid/test-outcome-minItems.json b/source/unified-test-format/tests/invalid/test-outcome-minItems.json
new file mode 100644
index 0000000000..aadf8e514a
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-minItems.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-outcome-minItems",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "outcome": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-outcome-minItems.yml b/source/unified-test-format/tests/invalid/test-outcome-minItems.yml
new file mode 100644
index 0000000000..f8d87d1f56
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-minItems.yml
@@ -0,0 +1,8 @@
+description: "test-outcome-minItems"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    outcome: []
diff --git a/source/unified-test-format/tests/invalid/test-outcome-type.json b/source/unified-test-format/tests/invalid/test-outcome-type.json
new file mode 100644
index 0000000000..e60c119d7e
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-outcome-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "outcome": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-outcome-type.yml b/source/unified-test-format/tests/invalid/test-outcome-type.yml
new file mode 100644
index 0000000000..cfc44183a5
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-outcome-type.yml
@@ -0,0 +1,8 @@
+description: "test-outcome-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    outcome: 0
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-items.json b/source/unified-test-format/tests/invalid/test-runOnRequirements-items.json
new file mode 100644
index 0000000000..866bebb51f
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-items.json
@@ -0,0 +1,13 @@
+{
+  "description": "test-runOnRequirements-items",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "runOnRequirements": [
+        0
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-items.yml b/source/unified-test-format/tests/invalid/test-runOnRequirements-items.yml
new file mode 100644
index 0000000000..2324fa8045
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-items.yml
@@ -0,0 +1,8 @@
+description: "test-runOnRequirements-items"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    runOnRequirements: [0]
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.json b/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.json
new file mode 100644
index 0000000000..d61f063849
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-runOnRequirements-minItems",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "runOnRequirements": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.yml b/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.yml
new file mode 100644
index 0000000000..2f3e0391ad
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-minItems.yml
@@ -0,0 +1,8 @@
+description: "test-runOnRequirements-minItems"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    runOnRequirements: []
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-type.json b/source/unified-test-format/tests/invalid/test-runOnRequirements-type.json
new file mode 100644
index 0000000000..5b25b1005d
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-runOnRequirements-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "runOnRequirements": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-runOnRequirements-type.yml b/source/unified-test-format/tests/invalid/test-runOnRequirements-type.yml
new file mode 100644
index 0000000000..12bd90e859
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-runOnRequirements-type.yml
@@ -0,0 +1,8 @@
+description: "test-runOnRequirements-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    runOnRequirements: 0
diff --git a/source/unified-test-format/tests/invalid/test-skipReason-type.json b/source/unified-test-format/tests/invalid/test-skipReason-type.json
new file mode 100644
index 0000000000..0408e76834
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-skipReason-type.json
@@ -0,0 +1,11 @@
+{
+  "description": "test-skipReason-type",
+  "schemaVersion": "1.0",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": [],
+      "skipReason": 0
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/test-skipReason-type.yml b/source/unified-test-format/tests/invalid/test-skipReason-type.yml
new file mode 100644
index 0000000000..7921aefc79
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/test-skipReason-type.yml
@@ -0,0 +1,8 @@
+description: "test-skipReason-type"
+
+schemaVersion: "1.0"
+
+tests:
+  - description: "foo"
+    operations: []
+    skipReason: 0
diff --git a/source/unified-test-format/tests/invalid/tests-items.json b/source/unified-test-format/tests/invalid/tests-items.json
new file mode 100644
index 0000000000..11f37469e4
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-items.json
@@ -0,0 +1,7 @@
+{
+  "description": "tests-items",
+  "schemaVersion": "1.0",
+  "tests": [
+    0
+  ]
+}
diff --git a/source/unified-test-format/tests/invalid/tests-items.yml b/source/unified-test-format/tests/invalid/tests-items.yml
new file mode 100644
index 0000000000..8c9829634c
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-items.yml
@@ -0,0 +1,5 @@
+description: "tests-items"
+
+schemaVersion: "1.0"
+
+tests: [0]
diff --git a/source/unified-test-format/tests/invalid/tests-minItems.json b/source/unified-test-format/tests/invalid/tests-minItems.json
new file mode 100644
index 0000000000..3f74f94af7
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-minItems.json
@@ -0,0 +1,5 @@
+{
+  "description": "tests-minItems",
+  "schemaVersion": "1.0",
+  "tests": []
+}
diff --git a/source/unified-test-format/tests/invalid/tests-minItems.yml b/source/unified-test-format/tests/invalid/tests-minItems.yml
new file mode 100644
index 0000000000..834120f835
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-minItems.yml
@@ -0,0 +1,5 @@
+description: "tests-minItems"
+
+schemaVersion: "1.0"
+
+tests: []
diff --git a/source/unified-test-format/tests/invalid/tests-required.json b/source/unified-test-format/tests/invalid/tests-required.json
new file mode 100644
index 0000000000..de4b2fd063
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-required.json
@@ -0,0 +1,4 @@
+{
+  "description": "tests-required",
+  "schemaVersion": "1.0"
+}
diff --git a/source/unified-test-format/tests/invalid/tests-required.yml b/source/unified-test-format/tests/invalid/tests-required.yml
new file mode 100644
index 0000000000..41c5072acf
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-required.yml
@@ -0,0 +1,3 @@
+description: "tests-required"
+
+schemaVersion: "1.0"
diff --git a/source/unified-test-format/tests/invalid/tests-type.json b/source/unified-test-format/tests/invalid/tests-type.json
new file mode 100644
index 0000000000..62d8194a41
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-type.json
@@ -0,0 +1,5 @@
+{
+  "description": "tests-type",
+  "schemaVersion": "1.0",
+  "tests": 0
+}
diff --git a/source/unified-test-format/tests/invalid/tests-type.yml b/source/unified-test-format/tests/invalid/tests-type.yml
new file mode 100644
index 0000000000..c16781a727
--- /dev/null
+++ b/source/unified-test-format/tests/invalid/tests-type.yml
@@ -0,0 +1,5 @@
+description: "tests-type"
+
+schemaVersion: "1.0"
+
+tests: 0
diff --git a/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.json b/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.json
new file mode 100644
index 0000000000..7f7f1978c3
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-bucket-database-undefined",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "bucket": {
+        "id": "bucket0",
+        "database": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.yml b/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.yml
new file mode 100644
index 0000000000..7aeda8e1ac
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-bucket-database-undefined.yml
@@ -0,0 +1,12 @@
+description: "entity-bucket-database-undefined"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - bucket:
+      id: &bucket0 "bucket0"
+      database: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.json b/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.json
new file mode 100644
index 0000000000..20b0733e34
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.json
@@ -0,0 +1,19 @@
+{
+  "description": "entity-collection-database-undefined",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "foo",
+        "collectionName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.yml b/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.yml
new file mode 100644
index 0000000000..a66b6ed292
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-collection-database-undefined.yml
@@ -0,0 +1,13 @@
+description: "entity-collection-database-undefined"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - collection:
+      id: &collection0 "collection0"
+      database: "foo"
+      collectionName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.json b/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.json
new file mode 100644
index 0000000000..0f8110e6d3
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.json
@@ -0,0 +1,19 @@
+{
+  "description": "entity-database-client-undefined",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "database": {
+        "id": "database0",
+        "client": "foo",
+        "databaseName": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.yml b/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.yml
new file mode 100644
index 0000000000..34b58cece5
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-database-client-undefined.yml
@@ -0,0 +1,13 @@
+description: "entity-database-client-undefined"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - database:
+      id: &database0 "database0"
+      client: "foo"
+      databaseName: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.json b/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.json
new file mode 100644
index 0000000000..260356436a
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.json
@@ -0,0 +1,18 @@
+{
+  "description": "entity-session-client-undefined",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "session": {
+        "id": "session0",
+        "client": "foo"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.yml b/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.yml
new file mode 100644
index 0000000000..16eaea46b7
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/entity-session-client-undefined.yml
@@ -0,0 +1,12 @@
+description: "entity-session-client-undefined"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - session:
+      id: &session0 "session0"
+      client: "foo"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.json b/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.json
new file mode 100644
index 0000000000..ea425fb568
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.json
@@ -0,0 +1,66 @@
+{
+  "description": "returnDocument-enum-invalid",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "test"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "coll"
+      }
+    }
+  ],
+  "tests": [
+    {
+      "description": "FindOneAndReplace returnDocument invalid enum value",
+      "operations": [
+        {
+          "name": "findOneAndReplace",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "replacement": {
+              "_id": 1,
+              "x": 111
+            },
+            "returnDocument": "invalid"
+          }
+        }
+      ]
+    },
+    {
+      "description": "FindOneAndUpdate returnDocument invalid enum value",
+      "operations": [
+        {
+          "name": "findOneAndUpdate",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "update": {
+              "$inc": {
+                "x": 1
+              }
+            },
+            "returnDocument": "invalid"
+          }
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.yml b/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.yml
new file mode 100644
index 0000000000..b877f5e965
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/returnDocument-enum-invalid.yml
@@ -0,0 +1,34 @@
+description: "returnDocument-enum-invalid"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 client0
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &databaseName test
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collectionName coll
+
+tests:
+  - description: "FindOneAndReplace returnDocument invalid enum value"
+    operations:
+      - name: findOneAndReplace
+        object: *collection0
+        arguments:
+          filter: { _id: 1 }
+          replacement: { _id: 1, x: 111 }
+          returnDocument: invalid
+
+  - description: "FindOneAndUpdate returnDocument invalid enum value"
+    operations:
+      - name: findOneAndUpdate
+        object: *collection0
+        arguments:
+          filter: { _id: 1 }
+          update: { $inc: { x : 1 }}
+          returnDocument: invalid
diff --git a/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.json b/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.json
new file mode 100644
index 0000000000..ceb5532917
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.json
@@ -0,0 +1,10 @@
+{
+  "description": "schemaVersion-unsupported",
+  "schemaVersion": "0.1",
+  "tests": [
+    {
+      "description": "foo",
+      "operations": []
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.yml b/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.yml
new file mode 100644
index 0000000000..0cb6994d24
--- /dev/null
+++ b/source/unified-test-format/tests/valid-fail/schemaVersion-unsupported.yml
@@ -0,0 +1,7 @@
+description: "schemaVersion-unsupported"
+
+schemaVersion: "0.1"
+
+tests:
+  - description: "foo"
+    operations: []
diff --git a/source/unified-test-format/tests/valid-pass/poc-change-streams.json b/source/unified-test-format/tests/valid-pass/poc-change-streams.json
new file mode 100644
index 0000000000..dc6e332e3e
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-change-streams.json
@@ -0,0 +1,410 @@
+{
+  "description": "poc-change-streams",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ],
+        "ignoreCommandMonitoringEvents": [
+          "getMore",
+          "killCursors"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "change-stream-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    },
+    {
+      "client": {
+        "id": "client1",
+        "useMultipleMongoses": false
+      }
+    },
+    {
+      "database": {
+        "id": "database1",
+        "client": "client1",
+        "databaseName": "change-stream-tests"
+      }
+    },
+    {
+      "database": {
+        "id": "database2",
+        "client": "client1",
+        "databaseName": "change-stream-tests-2"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection1",
+        "database": "database1",
+        "collectionName": "test"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection2",
+        "database": "database1",
+        "collectionName": "test2"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection3",
+        "database": "database2",
+        "collectionName": "test"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "change-stream-tests",
+      "documents": []
+    },
+    {
+      "collectionName": "test2",
+      "databaseName": "change-stream-tests",
+      "documents": []
+    },
+    {
+      "collectionName": "test",
+      "databaseName": "change-stream-tests-2",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "Executing a watch helper on a MongoClient results in notifications for changes to all collections in all databases in the cluster.",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "3.8.0",
+          "topologies": [
+            "replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "createChangeStream",
+          "object": "client0",
+          "saveResultAsEntity": "changeStream0"
+        },
+        {
+          "name": "insertOne",
+          "object": "collection2",
+          "arguments": {
+            "document": {
+              "x": 1
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection3",
+          "arguments": {
+            "document": {
+              "y": 1
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection1",
+          "arguments": {
+            "document": {
+              "z": 1
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test2"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "x": 1
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests-2",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "y": 1
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "z": 1
+            }
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": 1,
+                  "cursor": {},
+                  "pipeline": [
+                    {
+                      "$changeStream": {
+                        "allChangesForCluster": true,
+                        "fullDocument": {
+                          "$$unsetOrMatches": "default"
+                        }
+                      }
+                    }
+                  ]
+                },
+                "commandName": "aggregate",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Test consecutive resume",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.1.7",
+          "topologies": [
+            "replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 2
+              },
+              "data": {
+                "failCommands": [
+                  "getMore"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "createChangeStream",
+          "object": "collection0",
+          "arguments": {
+            "batchSize": 1
+          },
+          "saveResultAsEntity": "changeStream0"
+        },
+        {
+          "name": "insertOne",
+          "object": "collection1",
+          "arguments": {
+            "document": {
+              "x": 1
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection1",
+          "arguments": {
+            "document": {
+              "x": 2
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection1",
+          "arguments": {
+            "document": {
+              "x": 3
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "x": 1
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "x": 2
+            }
+          }
+        },
+        {
+          "name": "iterateUntilDocumentOrError",
+          "object": "changeStream0",
+          "expectResult": {
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "x": 3
+            }
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "test",
+                  "cursor": {
+                    "batchSize": 1
+                  },
+                  "pipeline": [
+                    {
+                      "$changeStream": {
+                        "fullDocument": {
+                          "$$unsetOrMatches": "default"
+                        }
+                      }
+                    }
+                  ]
+                },
+                "commandName": "aggregate",
+                "databaseName": "change-stream-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "test",
+                  "cursor": {
+                    "batchSize": 1
+                  },
+                  "pipeline": [
+                    {
+                      "$changeStream": {
+                        "fullDocument": {
+                          "$$unsetOrMatches": "default"
+                        },
+                        "resumeAfter": {
+                          "$$exists": true
+                        }
+                      }
+                    }
+                  ]
+                },
+                "commandName": "aggregate",
+                "databaseName": "change-stream-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "test",
+                  "cursor": {
+                    "batchSize": 1
+                  },
+                  "pipeline": [
+                    {
+                      "$changeStream": {
+                        "fullDocument": {
+                          "$$unsetOrMatches": "default"
+                        },
+                        "resumeAfter": {
+                          "$$exists": true
+                        }
+                      }
+                    }
+                  ]
+                },
+                "commandName": "aggregate",
+                "databaseName": "change-stream-tests"
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-change-streams.yml b/source/unified-test-format/tests/valid-pass/poc-change-streams.yml
new file mode 100644
index 0000000000..bdf83fdc60
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-change-streams.yml
@@ -0,0 +1,217 @@
+description: "poc-change-streams"
+
+schemaVersion: "1.0"
+
+createEntities:
+  # Entities for creating changeStreams
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+      # Original tests do not observe getMore commands but only because event
+      # assertions ignore extra events. killCursors is explicitly ignored.
+      ignoreCommandMonitoringEvents: [ getMore, killCursors ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name change-stream-tests
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name test
+  # Entities for executing insert operations
+  - client:
+      id: &client1 client1
+      useMultipleMongoses: false
+  - database:
+      id: &database1 database1
+      client: *client1
+      databaseName: &database1Name change-stream-tests
+  - database:
+      id: &database2 database2
+      client: *client1
+      databaseName: &database2Name change-stream-tests-2
+  - collection:
+      id: &collection1 collection1
+      database: *database1
+      collectionName: &collection1Name test
+  - collection:
+      id: &collection2 collection2
+      database: *database1
+      collectionName: &collection2Name test2
+  - collection:
+      id: &collection3 collection3
+      database: *database2
+      collectionName: &collection3Name test
+
+initialData:
+  - collectionName: *collection1Name
+    databaseName: *database1Name
+    documents: []
+  - collectionName: *collection2Name
+    databaseName: *database1Name
+    documents: []
+  - collectionName: *collection3Name
+    databaseName: *database2Name
+    documents: []
+
+tests:
+  - description: "Executing a watch helper on a MongoClient results in notifications for changes to all collections in all databases in the cluster."
+    runOnRequirements:
+      - minServerVersion: "3.8.0"
+        topologies: [ replicaset ]
+    operations:
+      - name: createChangeStream
+        object: *client0
+        saveResultAsEntity: &changeStream0 changeStream0
+      - name: insertOne
+        object: *collection2
+        arguments:
+          document: { x: 1 }
+      - name: insertOne
+        object: *collection3
+        arguments:
+          document: { y: 1 }
+      - name: insertOne
+        object: *collection1
+        arguments:
+          document: { z: 1 }
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database1Name
+            coll: *collection2Name
+          fullDocument:
+            _id: { $$type: objectId }
+            x: 1
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database2Name
+            coll: *collection3Name
+          fullDocument:
+            # Original tests did not include _id, but matching now only permits
+            # extra keys for root-level documents.
+            _id: { $$type: objectId }
+            y: 1
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database1Name
+            coll: *collection1Name
+          fullDocument:
+            _id: { $$type: objectId }
+            z: 1
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                aggregate: 1
+                cursor: {}
+                pipeline:
+                  - $changeStream:
+                      allChangesForCluster: true
+                      # Some drivers may send a default value for fullDocument
+                      # or omit it entirely (see: SPEC-1350).
+                      fullDocument: { $$unsetOrMatches: default }
+              commandName: aggregate
+              databaseName: admin
+
+  - description: "Test consecutive resume"
+    runOnRequirements:
+      - minServerVersion: "4.1.7"
+        topologies: [ replicaset ]
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 2 }
+            data:
+              failCommands: [ getMore ]
+              closeConnection: true
+      - name: createChangeStream
+        object: *collection0
+        arguments:
+          batchSize: 1
+        saveResultAsEntity: *changeStream0
+      - name: insertOne
+        object: *collection1
+        arguments:
+          document: { x: 1 }
+      - name: insertOne
+        object: *collection1
+        arguments:
+          document: { x: 2 }
+      - name: insertOne
+        object: *collection1
+        arguments:
+          document: { x: 3 }
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database1Name
+            coll: *collection1Name
+          fullDocument:
+            _id: { $$type: objectId }
+            x: 1
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database1Name
+            coll: *collection1Name
+          fullDocument:
+            _id: { $$type: objectId }
+            x: 2
+      - name: iterateUntilDocumentOrError
+        object: *changeStream0
+        expectResult:
+          operationType: insert
+          ns:
+            db: *database1Name
+            coll: *collection1Name
+          fullDocument:
+            _id: { $$type: objectId }
+            x: 3
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                aggregate: *collection1Name
+                cursor: { batchSize: 1 }
+                pipeline:
+                  - $changeStream:
+                      fullDocument: { $$unsetOrMatches: default }
+              commandName: aggregate
+              databaseName: *database1Name
+          # The original test only asserted the first command, since expected
+          # events were only an ordered subset. This file does ignore getMore
+          # commands but we must expect the subsequent aggregate commands, since
+          # each failed getMore will resume. While doing so we can also assert
+          # that those commands include a resume token.
+          - &resumingAggregate
+            commandStartedEvent:
+              command:
+                aggregate: *collection1Name
+                cursor: { batchSize: 1 }
+                pipeline:
+                  - $changeStream:
+                      fullDocument: { $$unsetOrMatches: default }
+                      resumeAfter: { $$exists: true }
+              commandName: aggregate
+              databaseName: *database0Name
+          - *resumingAggregate
diff --git a/source/unified-test-format/tests/valid-pass/poc-command-monitoring.json b/source/unified-test-format/tests/valid-pass/poc-command-monitoring.json
new file mode 100644
index 0000000000..499396e0ba
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-command-monitoring.json
@@ -0,0 +1,222 @@
+{
+  "description": "poc-command-monitoring",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          "commandStartedEvent",
+          "commandSucceededEvent",
+          "commandFailedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "command-monitoring-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "command-monitoring-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        },
+        {
+          "_id": 2,
+          "x": 22
+        },
+        {
+          "_id": 3,
+          "x": 33
+        },
+        {
+          "_id": 4,
+          "x": 44
+        },
+        {
+          "_id": 5,
+          "x": 55
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "A successful find event with a getmore and the server kills the cursor",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "3.1",
+          "topologies": [
+            "single",
+            "replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": {
+                "$gte": 1
+              }
+            },
+            "sort": {
+              "_id": 1
+            },
+            "batchSize": 3,
+            "limit": 4
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "test",
+                  "filter": {
+                    "_id": {
+                      "$gte": 1
+                    }
+                  },
+                  "sort": {
+                    "_id": 1
+                  },
+                  "batchSize": 3,
+                  "limit": 4
+                },
+                "commandName": "find",
+                "databaseName": "command-monitoring-tests"
+              }
+            },
+            {
+              "commandSucceededEvent": {
+                "reply": {
+                  "ok": 1,
+                  "cursor": {
+                    "id": {
+                      "$$type": [
+                        "int",
+                        "long"
+                      ]
+                    },
+                    "ns": "command-monitoring-tests.test",
+                    "firstBatch": [
+                      {
+                        "_id": 1,
+                        "x": 11
+                      },
+                      {
+                        "_id": 2,
+                        "x": 22
+                      },
+                      {
+                        "_id": 3,
+                        "x": 33
+                      }
+                    ]
+                  }
+                },
+                "commandName": "find"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "getMore": {
+                    "$$type": [
+                      "int",
+                      "long"
+                    ]
+                  },
+                  "collection": "test",
+                  "batchSize": 1
+                },
+                "commandName": "getMore",
+                "databaseName": "command-monitoring-tests"
+              }
+            },
+            {
+              "commandSucceededEvent": {
+                "reply": {
+                  "ok": 1,
+                  "cursor": {
+                    "id": 0,
+                    "ns": "command-monitoring-tests.test",
+                    "nextBatch": [
+                      {
+                        "_id": 4,
+                        "x": 44
+                      }
+                    ]
+                  }
+                },
+                "commandName": "getMore"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "A failed find event",
+      "operations": [
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "$or": true
+            }
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "test",
+                  "filter": {
+                    "$or": true
+                  }
+                },
+                "commandName": "find",
+                "databaseName": "command-monitoring-tests"
+              }
+            },
+            {
+              "commandFailedEvent": {
+                "commandName": "find"
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-command-monitoring.yml b/source/unified-test-format/tests/valid-pass/poc-command-monitoring.yml
new file mode 100644
index 0000000000..19a282327c
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-command-monitoring.yml
@@ -0,0 +1,101 @@
+description: "poc-command-monitoring"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 client0
+      observeEvents:
+        - commandStartedEvent
+        - commandSucceededEvent
+        - commandFailedEvent
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name command-monitoring-tests
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name test
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1, x: 11 }
+      - { _id: 2, x: 22 }
+      - { _id: 3, x: 33 }
+      - { _id: 4, x: 44 }
+      - { _id: 5, x: 55 }
+
+tests:
+  - description: "A successful find event with a getmore and the server kills the cursor"
+    runOnRequirements:
+      - minServerVersion: "3.1"
+        topologies: [ single, replicaset ]
+    operations:
+      - name: find
+        object: *collection0
+        arguments:
+          filter: { _id: { $gte: 1 }}
+          sort: { _id: 1 }
+          batchSize: 3
+          limit: 4
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                find: *collection0Name
+                filter: { _id: { $gte : 1 } }
+                sort: { _id: 1 }
+                batchSize: 3
+                limit: 4
+              commandName: find
+              databaseName: *database0Name
+          - commandSucceededEvent:
+              reply:
+                ok: 1
+                cursor:
+                  id: { $$type: [ int, long ] }
+                  ns: &namespace command-monitoring-tests.test
+                  firstBatch:
+                    - { _id: 1, x: 11 }
+                    - { _id: 2, x: 22 }
+                    - { _id: 3, x: 33 }
+              commandName: find
+          - commandStartedEvent:
+              command:
+                getMore: { $$type: [ int, long ] }
+                collection: *collection0Name
+                batchSize: 1
+              commandName: getMore
+              databaseName: *database0Name
+          - commandSucceededEvent:
+              reply:
+                ok: 1
+                cursor:
+                  id: 0
+                  ns: *namespace
+                  nextBatch:
+                    - { _id: 4, x: 44 }
+              commandName: getMore
+
+  - description: "A failed find event"
+    operations:
+      - name: find
+        object: *collection0
+        arguments:
+          filter: { $or: true }
+        expectError: { isError: true }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                find: *collection0Name
+                filter: { $or: true }
+              commandName: find
+              databaseName: *database0Name
+          - commandFailedEvent:
+              commandName: find
diff --git a/source/unified-test-format/tests/valid-pass/poc-crud.json b/source/unified-test-format/tests/valid-pass/poc-crud.json
new file mode 100644
index 0000000000..2ed86d6150
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-crud.json
@@ -0,0 +1,446 @@
+{
+  "description": "poc-crud",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "crud-tests"
+      }
+    },
+    {
+      "database": {
+        "id": "database1",
+        "client": "client0",
+        "databaseName": "admin"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "coll0"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection1",
+        "database": "database0",
+        "collectionName": "coll1"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection2",
+        "database": "database0",
+        "collectionName": "coll2",
+        "collectionOptions": {
+          "readConcern": {
+            "level": "majority"
+          }
+        }
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "coll0",
+      "databaseName": "crud-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        },
+        {
+          "_id": 2,
+          "x": 22
+        }
+      ]
+    },
+    {
+      "collectionName": "coll1",
+      "databaseName": "crud-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        }
+      ]
+    },
+    {
+      "collectionName": "coll2",
+      "databaseName": "crud-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        },
+        {
+          "_id": 2,
+          "x": 22
+        },
+        {
+          "_id": 3,
+          "x": 33
+        }
+      ]
+    },
+    {
+      "collectionName": "aggregate_out",
+      "databaseName": "crud-tests",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "BulkWrite with mixed ordered operations",
+      "operations": [
+        {
+          "name": "bulkWrite",
+          "object": "collection0",
+          "arguments": {
+            "requests": [
+              {
+                "insertOne": {
+                  "document": {
+                    "_id": 3,
+                    "x": 33
+                  }
+                }
+              },
+              {
+                "updateOne": {
+                  "filter": {
+                    "_id": 2
+                  },
+                  "update": {
+                    "$inc": {
+                      "x": 1
+                    }
+                  }
+                }
+              },
+              {
+                "updateMany": {
+                  "filter": {
+                    "_id": {
+                      "$gt": 1
+                    }
+                  },
+                  "update": {
+                    "$inc": {
+                      "x": 1
+                    }
+                  }
+                }
+              },
+              {
+                "insertOne": {
+                  "document": {
+                    "_id": 4,
+                    "x": 44
+                  }
+                }
+              },
+              {
+                "deleteMany": {
+                  "filter": {
+                    "x": {
+                      "$nin": [
+                        24,
+                        34
+                      ]
+                    }
+                  }
+                }
+              },
+              {
+                "replaceOne": {
+                  "filter": {
+                    "_id": 4
+                  },
+                  "replacement": {
+                    "_id": 4,
+                    "x": 44
+                  },
+                  "upsert": true
+                }
+              }
+            ],
+            "ordered": true
+          },
+          "expectResult": {
+            "deletedCount": 2,
+            "insertedCount": 2,
+            "insertedIds": {
+              "$$unsetOrMatches": {
+                "0": 3,
+                "3": 4
+              }
+            },
+            "matchedCount": 3,
+            "modifiedCount": 3,
+            "upsertedCount": 1,
+            "upsertedIds": {
+              "5": 4
+            }
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll0",
+          "databaseName": "crud-tests",
+          "documents": [
+            {
+              "_id": 2,
+              "x": 24
+            },
+            {
+              "_id": 3,
+              "x": 34
+            },
+            {
+              "_id": 4,
+              "x": 44
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "InsertMany continue-on-error behavior with unordered (duplicate key in requests)",
+      "operations": [
+        {
+          "name": "insertMany",
+          "object": "collection1",
+          "arguments": {
+            "documents": [
+              {
+                "_id": 2,
+                "x": 22
+              },
+              {
+                "_id": 2,
+                "x": 22
+              },
+              {
+                "_id": 3,
+                "x": 33
+              }
+            ],
+            "ordered": false
+          },
+          "expectError": {
+            "expectResult": {
+              "deletedCount": 0,
+              "insertedCount": 2,
+              "matchedCount": 0,
+              "modifiedCount": 0,
+              "upsertedCount": 0,
+              "upsertedIds": {}
+            }
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll1",
+          "databaseName": "crud-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "ReplaceOne prohibits atomic modifiers",
+      "operations": [
+        {
+          "name": "replaceOne",
+          "object": "collection1",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "replacement": {
+              "$set": {
+                "x": 22
+              }
+            }
+          },
+          "expectError": {
+            "isClientError": true
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": []
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll1",
+          "databaseName": "crud-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "readConcern majority with out stage",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.1.0",
+          "topologies": [
+            "replicaset",
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "aggregate",
+          "object": "collection2",
+          "arguments": {
+            "pipeline": [
+              {
+                "$sort": {
+                  "x": 1
+                }
+              },
+              {
+                "$match": {
+                  "_id": {
+                    "$gt": 1
+                  }
+                }
+              },
+              {
+                "$out": "aggregate_out"
+              }
+            ]
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "coll2",
+                  "pipeline": [
+                    {
+                      "$sort": {
+                        "x": 1
+                      }
+                    },
+                    {
+                      "$match": {
+                        "_id": {
+                          "$gt": 1
+                        }
+                      }
+                    },
+                    {
+                      "$out": "aggregate_out"
+                    }
+                  ],
+                  "readConcern": {
+                    "level": "majority"
+                  }
+                },
+                "commandName": "aggregate",
+                "databaseName": "crud-tests"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "aggregate_out",
+          "databaseName": "crud-tests",
+          "documents": [
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Aggregate with $listLocalSessions",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "3.6.0"
+        }
+      ],
+      "operations": [
+        {
+          "name": "aggregate",
+          "object": "database1",
+          "arguments": {
+            "pipeline": [
+              {
+                "$listLocalSessions": {}
+              },
+              {
+                "$limit": 1
+              },
+              {
+                "$addFields": {
+                  "dummy": "dummy field"
+                }
+              },
+              {
+                "$project": {
+                  "_id": 0,
+                  "dummy": 1
+                }
+              }
+            ]
+          },
+          "expectResult": [
+            {
+              "dummy": "dummy field"
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-crud.yml b/source/unified-test-format/tests/valid-pass/poc-crud.yml
new file mode 100644
index 0000000000..7d101a077a
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-crud.yml
@@ -0,0 +1,183 @@
+description: "poc-crud"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 client0
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name crud-tests
+  - database:
+      id: &database1 database1
+      client: *client0
+      databaseName: &database1Name admin
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name coll0
+  - collection:
+      id: &collection1 collection1
+      database: *database0
+      collectionName: &collection1Name coll1
+  - collection:
+      id: &collection2 collection2
+      database: *database0
+      collectionName: &collection2Name coll2
+      collectionOptions:
+        readConcern: { level: majority }
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1, x: 11 }
+      - { _id: 2, x: 22 }
+  - collectionName: *collection1Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1, x: 11 }
+  - collectionName: *collection2Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1, x: 11 }
+      - { _id: 2, x: 22 }
+      - { _id: 3, x: 33 }
+  - collectionName: &out aggregate_out
+    databaseName: *database0Name
+    documents: []
+
+tests:
+  - description: "BulkWrite with mixed ordered operations"
+    operations:
+      - name: bulkWrite
+        object: *collection0
+        arguments:
+          requests:
+            - insertOne:
+                document: { _id: 3, x: 33 }
+            - updateOne:
+                filter: { _id: 2 }
+                update: { $inc: { x: 1 } }
+            - updateMany:
+                filter: { _id: { $gt: 1 } }
+                update: { $inc: { x: 1 } }
+            - insertOne:
+                document: { _id: 4, x: 44 }
+            - deleteMany:
+                filter: { x: { $nin: [ 24, 34 ] } }
+            - replaceOne:
+                filter: { _id: 4 }
+                replacement: { _id: 4, x: 44 }
+                upsert: true
+          ordered: true
+        expectResult:
+          deletedCount: 2
+          insertedCount: 2
+          insertedIds: { $$unsetOrMatches: { 0: 3, 3: 4 } }
+          matchedCount: 3
+          modifiedCount: 3
+          upsertedCount: 1
+          upsertedIds: { 5: 4 }
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - {_id: 2, x: 24 }
+          - {_id: 3, x: 34 }
+          - {_id: 4, x: 44 }
+
+  - description: "InsertMany continue-on-error behavior with unordered (duplicate key in requests)"
+    operations:
+      - name: insertMany
+        object: *collection1
+        arguments:
+          documents:
+            - { _id: 2, x: 22 }
+            - { _id: 2, x: 22 }
+            - { _id: 3, x: 33 }
+          ordered: false
+        expectError:
+          expectResult:
+            deletedCount: 0
+            insertedCount: 2
+            # Since the map of insertedIds is generated before execution it
+            # could indicate inserts that did not actually succeed. We omit
+            # this field rather than expect drivers to provide an accurate
+            # map filtered by write errors.
+            matchedCount: 0
+            modifiedCount: 0
+            upsertedCount: 0
+            upsertedIds: { }
+    outcome:
+      - collectionName: *collection1Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+          - { _id: 3, x: 33 }
+
+  - description: "ReplaceOne prohibits atomic modifiers"
+    operations:
+      - name: replaceOne
+        object: *collection1
+        arguments:
+          filter: { _id: 1 }
+          replacement: { $set: { x: 22 }}
+        expectError:
+          isClientError: true
+    expectEvents:
+      - client: *client0
+        events: []
+    outcome:
+      - collectionName: *collection1Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1, x: 11 }
+
+  - description: "readConcern majority with out stage"
+    runOnRequirements:
+      - minServerVersion: "4.1.0"
+        topologies: [ replicaset, sharded-replicaset ]
+    operations:
+      - name: aggregate
+        object: *collection2
+        arguments:
+          pipeline: &pipeline
+            - $sort: { x : 1 }
+            - $match: { _id: { $gt: 1 } }
+            - $out: *out
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                aggregate: *collection2Name
+                pipeline: *pipeline
+                readConcern: { level: majority }
+              # The following two assertions were not in the original test
+              commandName: aggregate
+              databaseName: *database0Name
+    outcome:
+      - collectionName: *out
+        databaseName: *database0Name
+        documents:
+          - { _id: 2, x: 22 }
+          - { _id: 3, x: 33 }
+
+  - description: "Aggregate with $listLocalSessions"
+    runOnRequirements:
+      - minServerVersion: "3.6.0"
+    operations:
+      - name: aggregate
+        object: *database1
+        arguments:
+          pipeline:
+            - $listLocalSessions: { }
+            - $limit: 1
+            - $addFields: { dummy: "dummy field"}
+            - $project: { _id: 0, dummy: 1}
+        expectResult:
+          - { dummy: "dummy field" }
diff --git a/source/unified-test-format/tests/valid-pass/poc-gridfs.json b/source/unified-test-format/tests/valid-pass/poc-gridfs.json
new file mode 100644
index 0000000000..c04ed89a7c
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-gridfs.json
@@ -0,0 +1,299 @@
+{
+  "description": "poc-gridfs",
+  "schemaVersion": "1.0",
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0"
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "gridfs-tests"
+      }
+    },
+    {
+      "bucket": {
+        "id": "bucket0",
+        "database": "database0"
+      }
+    },
+    {
+      "collection": {
+        "id": "bucket0_files_collection",
+        "database": "database0",
+        "collectionName": "fs.files"
+      }
+    },
+    {
+      "collection": {
+        "id": "bucket0_chunks_collection",
+        "database": "database0",
+        "collectionName": "fs.chunks"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "fs.files",
+      "databaseName": "gridfs-tests",
+      "documents": [
+        {
+          "_id": {
+            "$oid": "000000000000000000000005"
+          },
+          "length": 10,
+          "chunkSize": 4,
+          "uploadDate": {
+            "$date": "1970-01-01T00:00:00.000Z"
+          },
+          "md5": "57d83cd477bfb1ccd975ab33d827a92b",
+          "filename": "length-10",
+          "contentType": "application/octet-stream",
+          "aliases": [],
+          "metadata": {}
+        }
+      ]
+    },
+    {
+      "collectionName": "fs.chunks",
+      "databaseName": "gridfs-tests",
+      "documents": [
+        {
+          "_id": {
+            "$oid": "000000000000000000000005"
+          },
+          "files_id": {
+            "$oid": "000000000000000000000005"
+          },
+          "n": 0,
+          "data": {
+            "$binary": {
+              "base64": "ESIzRA==",
+              "subType": "00"
+            }
+          }
+        },
+        {
+          "_id": {
+            "$oid": "000000000000000000000006"
+          },
+          "files_id": {
+            "$oid": "000000000000000000000005"
+          },
+          "n": 1,
+          "data": {
+            "$binary": {
+              "base64": "VWZ3iA==",
+              "subType": "00"
+            }
+          }
+        },
+        {
+          "_id": {
+            "$oid": "000000000000000000000007"
+          },
+          "files_id": {
+            "$oid": "000000000000000000000005"
+          },
+          "n": 2,
+          "data": {
+            "$binary": {
+              "base64": "mao=",
+              "subType": "00"
+            }
+          }
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "Delete when length is 10",
+      "operations": [
+        {
+          "name": "delete",
+          "object": "bucket0",
+          "arguments": {
+            "id": {
+              "$oid": "000000000000000000000005"
+            }
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "fs.files",
+          "databaseName": "gridfs-tests",
+          "documents": []
+        },
+        {
+          "collectionName": "fs.chunks",
+          "databaseName": "gridfs-tests",
+          "documents": []
+        }
+      ]
+    },
+    {
+      "description": "Download when there are three chunks",
+      "operations": [
+        {
+          "name": "download",
+          "object": "bucket0",
+          "arguments": {
+            "id": {
+              "$oid": "000000000000000000000005"
+            }
+          },
+          "expectResult": {
+            "$$matchesHexBytes": "112233445566778899aa"
+          }
+        }
+      ]
+    },
+    {
+      "description": "Download when files entry does not exist",
+      "operations": [
+        {
+          "name": "download",
+          "object": "bucket0",
+          "arguments": {
+            "id": {
+              "$oid": "000000000000000000000000"
+            }
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ]
+    },
+    {
+      "description": "Download when an intermediate chunk is missing",
+      "operations": [
+        {
+          "name": "deleteOne",
+          "object": "bucket0_chunks_collection",
+          "arguments": {
+            "filter": {
+              "files_id": {
+                "$oid": "000000000000000000000005"
+              },
+              "n": 1
+            }
+          },
+          "expectResult": {
+            "deletedCount": 1
+          }
+        },
+        {
+          "name": "download",
+          "object": "bucket0",
+          "arguments": {
+            "id": {
+              "$oid": "000000000000000000000005"
+            }
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ]
+    },
+    {
+      "description": "Upload when length is 5",
+      "operations": [
+        {
+          "name": "upload",
+          "object": "bucket0",
+          "arguments": {
+            "filename": "filename",
+            "source": {
+              "$$hexBytes": "1122334455"
+            },
+            "chunkSizeBytes": 4
+          },
+          "expectResult": {
+            "$$type": "objectId"
+          },
+          "saveResultAsEntity": "oid0"
+        },
+        {
+          "name": "find",
+          "object": "bucket0_files_collection",
+          "arguments": {
+            "filter": {},
+            "sort": {
+              "uploadDate": -1
+            },
+            "limit": 1
+          },
+          "expectResult": [
+            {
+              "_id": {
+                "$$matchesEntity": "oid0"
+              },
+              "length": 5,
+              "chunkSize": 4,
+              "uploadDate": {
+                "$$type": "date"
+              },
+              "md5": "283d4fea5dded59cf837d3047328f5af",
+              "filename": "filename"
+            }
+          ]
+        },
+        {
+          "name": "find",
+          "object": "bucket0_chunks_collection",
+          "arguments": {
+            "filter": {
+              "_id": {
+                "$gt": {
+                  "$oid": "000000000000000000000007"
+                }
+              }
+            },
+            "sort": {
+              "n": 1
+            }
+          },
+          "expectResult": [
+            {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "files_id": {
+                "$$matchesEntity": "oid0"
+              },
+              "n": 0,
+              "data": {
+                "$binary": {
+                  "base64": "ESIzRA==",
+                  "subType": "00"
+                }
+              }
+            },
+            {
+              "_id": {
+                "$$type": "objectId"
+              },
+              "files_id": {
+                "$$matchesEntity": "oid0"
+              },
+              "n": 1,
+              "data": {
+                "$binary": {
+                  "base64": "VQ==",
+                  "subType": "00"
+                }
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-gridfs.yml b/source/unified-test-format/tests/valid-pass/poc-gridfs.yml
new file mode 100644
index 0000000000..8a0478658b
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-gridfs.yml
@@ -0,0 +1,154 @@
+description: "poc-gridfs"
+
+schemaVersion: "1.0"
+
+createEntities:
+  - client:
+      id: &client0 client0
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name gridfs-tests
+  - bucket:
+      id: &bucket0 bucket0
+      database: *database0
+  - collection:
+      id: &bucket0_files_collection bucket0_files_collection
+      database: *database0
+      collectionName: &bucket0_files_collectionName fs.files
+  - collection:
+      id: &bucket0_chunks_collection bucket0_chunks_collection
+      database: *database0
+      collectionName: &bucket0_chunks_collectionName fs.chunks
+
+initialData:
+  - collectionName: *bucket0_files_collectionName
+    databaseName: *database0Name
+    documents:
+      - _id: { $oid: "000000000000000000000005" }
+        length: 10
+        chunkSize: 4
+        uploadDate: { $date: "1970-01-01T00:00:00.000Z" }
+        md5: "57d83cd477bfb1ccd975ab33d827a92b"
+        filename: "length-10"
+        contentType: "application/octet-stream"
+        aliases: []
+        metadata: {}
+  - collectionName: *bucket0_chunks_collectionName
+    databaseName: *database0Name
+    documents:
+      - _id: { $oid: "000000000000000000000005" }
+        files_id: { $oid: "000000000000000000000005" }
+        n: 0
+        data: { $binary: { base64: "ESIzRA==", subType: "00" } } # hex: 11223344
+      - _id: { $oid: "000000000000000000000006" }
+        files_id: { $oid: "000000000000000000000005" }
+        n: 1
+        data: { $binary: { base64: "VWZ3iA==", subType: "00" } } # hex: 55667788
+      - _id: { $oid: "000000000000000000000007" }
+        files_id: { $oid: "000000000000000000000005" }
+        n: 2
+        data: { $binary: { base64: "mao=", subType: "00" } } # hex: 99aa
+
+tests:
+  # Changed from original test ("length is 8") to operate on same initialData
+  - description: "Delete when length is 10"
+    operations:
+      - name: delete
+        object: *bucket0
+        arguments:
+          id: { $oid: "000000000000000000000005" }
+    # Original test uses "assert.data" syntax to modify outcome collection for
+    # comparison. This can be accomplished using "outcome" directly.
+    outcome:
+      - collectionName: *bucket0_files_collectionName
+        databaseName: *database0Name
+        documents: []
+      - collectionName: *bucket0_chunks_collectionName
+        databaseName: *database0Name
+        documents: []
+
+  - description: "Download when there are three chunks"
+    operations:
+      # Original test uses "download" operation. We use an explicit operation
+      # that returns a stream and then assert the contents of that stream.
+      - name: download
+        object: *bucket0
+        arguments:
+          id: { $oid: "000000000000000000000005" }
+        expectResult: { $$matchesHexBytes: "112233445566778899aa" }
+
+  - description: "Download when files entry does not exist"
+    operations:
+      - name: download
+        object: *bucket0
+        arguments:
+          id: { $oid: "000000000000000000000000" }
+        # Original test expects "FileNotFound" error, which isn't specified
+        expectError: { isError: true }
+
+  - description: "Download when an intermediate chunk is missing"
+    operations:
+      # Original test uses "arrange" syntax to modify initialData. This can be
+      # accomplished as a delete operation on the chunks collection.
+      - name: deleteOne
+        object: *bucket0_chunks_collection
+        arguments:
+          filter:
+            files_id: { $oid: "000000000000000000000005" }
+            n: 1
+        expectResult:
+          deletedCount: 1
+      - name: download
+        object: *bucket0
+        arguments:
+          id: { $oid: "000000000000000000000005" }
+        # Original test expects "ChunkIsMissing" error, which isn't specified
+        expectError: { isError: true }
+
+  - description: "Upload when length is 5"
+    operations:
+      # Original test uses "upload" operation. We use an explicit operation
+      # that takes a stream, which has been created from the expected hex bytes.
+      - name: upload
+        object: *bucket0
+        arguments:
+          filename: filename
+          source: { $$hexBytes: "1122334455" }
+          chunkSizeBytes: 4
+        # Original test references the result directly in "assert.data". Here,
+        # we need to save the result as an entity, which we can later reference.
+        expectResult: { $$type: objectId }
+        saveResultAsEntity: &oid0 oid0
+      # "outcome" does not allow operators, but we can perform the assertions
+      # with separate find operations.
+      - name: find
+        object: *bucket0_files_collection
+        arguments:
+          filter: {}
+          sort: { uploadDate: -1 }
+          limit: 1
+        expectResult:
+          - _id: { $$matchesEntity: *oid0 }
+            length: 5
+            chunkSize: 4
+            uploadDate: { $$type: date }
+            md5: "283d4fea5dded59cf837d3047328f5af"
+            filename: filename
+      - name: find
+        object: *bucket0_chunks_collection
+        arguments:
+          # We cannot use the saved ObjectId when querying, but filtering by a
+          # non-zero timestamp will exclude initialData and sort can return the
+          # expected chunks in order.
+          filter: { _id: { $gt: { $oid: "000000000000000000000007" } } }
+          sort: { n: 1 }
+        expectResult:
+          - _id: { $$type: objectId }
+            files_id: { $$matchesEntity: *oid0 }
+            n: 0
+            data: { $binary: { base64: "ESIzRA==", subType: "00" } } # hex 11223344
+          - _id: { $$type: objectId }
+            files_id: { $$matchesEntity: *oid0 }
+            n: 1
+            data: { $binary: { base64: "VQ==", subType: "00" } } # hex 55
diff --git a/source/unified-test-format/tests/valid-pass/poc-retryable-reads.json b/source/unified-test-format/tests/valid-pass/poc-retryable-reads.json
new file mode 100644
index 0000000000..2b65d501a7
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-retryable-reads.json
@@ -0,0 +1,433 @@
+{
+  "description": "poc-retryable-reads",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.0",
+      "topologies": [
+        "single",
+        "replicaset"
+      ]
+    },
+    {
+      "minServerVersion": "4.1.7",
+      "topologies": [
+        "sharded"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "client": {
+        "id": "client1",
+        "uriOptions": {
+          "retryReads": false
+        },
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "retryable-reads-tests"
+      }
+    },
+    {
+      "database": {
+        "id": "database1",
+        "client": "client1",
+        "databaseName": "retryable-reads-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "coll"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection1",
+        "database": "database1",
+        "collectionName": "coll"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "coll",
+      "databaseName": "retryable-reads-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        },
+        {
+          "_id": 2,
+          "x": 22
+        },
+        {
+          "_id": 3,
+          "x": 33
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "Aggregate succeeds after InterruptedAtShutdown",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "aggregate"
+                ],
+                "errorCode": 11600
+              }
+            }
+          }
+        },
+        {
+          "name": "aggregate",
+          "object": "collection0",
+          "arguments": {
+            "pipeline": [
+              {
+                "$match": {
+                  "_id": {
+                    "$gt": 1
+                  }
+                }
+              },
+              {
+                "$sort": {
+                  "x": 1
+                }
+              }
+            ]
+          },
+          "expectResult": [
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            }
+          ]
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "coll",
+                  "pipeline": [
+                    {
+                      "$match": {
+                        "_id": {
+                          "$gt": 1
+                        }
+                      }
+                    },
+                    {
+                      "$sort": {
+                        "x": 1
+                      }
+                    }
+                  ]
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "aggregate": "coll",
+                  "pipeline": [
+                    {
+                      "$match": {
+                        "_id": {
+                          "$gt": 1
+                        }
+                      }
+                    },
+                    {
+                      "$sort": {
+                        "x": 1
+                      }
+                    }
+                  ]
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Find succeeds on second attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "find"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {},
+            "sort": {
+              "_id": 1
+            },
+            "limit": 2
+          },
+          "expectResult": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            }
+          ]
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "coll",
+                  "filter": {},
+                  "sort": {
+                    "_id": 1
+                  },
+                  "limit": 2
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "coll",
+                  "filter": {},
+                  "sort": {
+                    "_id": 1
+                  },
+                  "limit": 2
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Find fails on first attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "find"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "find",
+          "object": "collection1",
+          "arguments": {
+            "filter": {}
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client1",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "coll",
+                  "filter": {}
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Find fails on second attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 2
+              },
+              "data": {
+                "failCommands": [
+                  "find"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {}
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "coll",
+                  "filter": {}
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "coll",
+                  "filter": {}
+                },
+                "databaseName": "retryable-reads-tests"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "ListDatabases succeeds on second attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "listDatabases"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "listDatabases",
+          "object": "client0"
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "listDatabases": 1
+                }
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "listDatabases": 1
+                }
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-retryable-reads.yml b/source/unified-test-format/tests/valid-pass/poc-retryable-reads.yml
new file mode 100644
index 0000000000..c1ea7ec696
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-retryable-reads.yml
@@ -0,0 +1,193 @@
+description: "poc-retryable-reads"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "4.0"
+    topologies: [ single, replicaset ]
+  - minServerVersion: "4.1.7"
+    topologies: [ sharded ]
+
+createEntities:
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+  - client:
+      id: &client1 client1
+      uriOptions: { retryReads: false }
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &databaseName retryable-reads-tests
+  - database:
+      id: &database1 database1
+      client: *client1
+      databaseName: *databaseName
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collectionName coll
+  - collection:
+      id: &collection1 collection1
+      database: *database1
+      collectionName: *collectionName
+
+initialData:
+  - collectionName: *collectionName
+    databaseName: *databaseName
+    documents:
+      - {_id: 1, x: 11}
+      - {_id: 2, x: 22}
+      - {_id: 3, x: 33}
+
+tests:
+  - description: "Aggregate succeeds after InterruptedAtShutdown"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ aggregate ]
+              errorCode: 11600 # InterruptedAtShutdown
+      - name: aggregate
+        object: *collection0
+        arguments:
+          pipeline: &pipeline
+            - $match: { _id: { $gt: 1 } }
+            - $sort: { x: 1 }
+        expectResult:
+          - { _id: 2, x: 22 }
+          - { _id: 3, x: 33 }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                aggregate: *collectionName
+                pipeline: *pipeline
+              databaseName: *databaseName
+          - commandStartedEvent:
+              command:
+                aggregate: *collectionName
+                pipeline: *pipeline
+              databaseName: *databaseName
+
+  - description: "Find succeeds on second attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ find ]
+              closeConnection: true
+      # Find options and expected result changed to use common initialData
+      - name: find
+        object: collection0
+        arguments:
+          filter: {}
+          sort: { _id: 1 }
+          limit: 2
+        expectResult:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+    expectEvents:
+      - client: *client0
+        events:
+          - &findAttempt
+            commandStartedEvent:
+              command:
+                find: *collectionName
+                filter: {}
+                sort: { _id: 1 }
+                limit: 2
+              databaseName: *databaseName
+          - *findAttempt
+
+  - description: "Find fails on first attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ find ]
+              closeConnection: true
+      - name: find
+        object: collection1 # client uses retryReads=false
+        arguments:
+          filter: {}
+          # Other arguments in the original test are not relevant
+        expectError: { isError: true }
+    expectEvents:
+      - client: *client1
+        events:
+          - commandStartedEvent:
+              command:
+                find: *collectionName
+                filter: {}
+              databaseName: *databaseName
+
+  - description: "Find fails on second attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 2 }
+            data:
+              failCommands: [ find ]
+              closeConnection: true
+      - name: find
+        object: collection0
+        arguments:
+          filter: {}
+          # Other arguments in the original test are not relevant
+        expectError: { isError: true }
+    expectEvents:
+      - client: *client0
+        events:
+          - &findAttempt
+            commandStartedEvent:
+              command:
+                find: *collectionName
+                filter: {}
+              databaseName: *databaseName
+          - *findAttempt
+
+  - description: "ListDatabases succeeds on second attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ listDatabases ]
+              closeConnection: true
+      - name: listDatabases
+        object: *client0
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command: { listDatabases: 1 }
+          - commandStartedEvent:
+              command: { listDatabases: 1 }
diff --git a/source/unified-test-format/tests/valid-pass/poc-retryable-writes.json b/source/unified-test-format/tests/valid-pass/poc-retryable-writes.json
new file mode 100644
index 0000000000..e64ce1bcee
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-retryable-writes.json
@@ -0,0 +1,481 @@
+{
+  "description": "poc-retryable-writes",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "3.6",
+      "topologies": [
+        "replicaset"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "client": {
+        "id": "client1",
+        "uriOptions": {
+          "retryWrites": false
+        },
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "retryable-writes-tests"
+      }
+    },
+    {
+      "database": {
+        "id": "database1",
+        "client": "client1",
+        "databaseName": "retryable-writes-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "coll"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection1",
+        "database": "database1",
+        "collectionName": "coll"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "coll",
+      "databaseName": "retryable-writes-tests",
+      "documents": [
+        {
+          "_id": 1,
+          "x": 11
+        },
+        {
+          "_id": 2,
+          "x": 22
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "FindOneAndUpdate is committed on first attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "onPrimaryTransactionalWrite",
+              "mode": {
+                "times": 1
+              }
+            }
+          }
+        },
+        {
+          "name": "findOneAndUpdate",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "update": {
+              "$inc": {
+                "x": 1
+              }
+            },
+            "returnDocument": "Before"
+          },
+          "expectResult": {
+            "_id": 1,
+            "x": 11
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 12
+            },
+            {
+              "_id": 2,
+              "x": 22
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "FindOneAndUpdate is not committed on first attempt",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "onPrimaryTransactionalWrite",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failBeforeCommitExceptionCode": 1
+              }
+            }
+          }
+        },
+        {
+          "name": "findOneAndUpdate",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "update": {
+              "$inc": {
+                "x": 1
+              }
+            },
+            "returnDocument": "Before"
+          },
+          "expectResult": {
+            "_id": 1,
+            "x": 11
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 12
+            },
+            {
+              "_id": 2,
+              "x": 22
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "FindOneAndUpdate is never committed",
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "onPrimaryTransactionalWrite",
+              "mode": {
+                "times": 2
+              },
+              "data": {
+                "failBeforeCommitExceptionCode": 1
+              }
+            }
+          }
+        },
+        {
+          "name": "findOneAndUpdate",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": 1
+            },
+            "update": {
+              "$inc": {
+                "x": 1
+              }
+            },
+            "returnDocument": "Before"
+          },
+          "expectError": {
+            "isError": true
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "InsertMany succeeds after PrimarySteppedDown",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.0",
+          "topologies": [
+            "replicaset"
+          ]
+        },
+        {
+          "minServerVersion": "4.1.7",
+          "topologies": [
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "errorCode": 189,
+                "errorLabels": [
+                  "RetryableWriteError"
+                ]
+              }
+            }
+          }
+        },
+        {
+          "name": "insertMany",
+          "object": "collection0",
+          "arguments": {
+            "documents": [
+              {
+                "_id": 3,
+                "x": 33
+              },
+              {
+                "_id": 4,
+                "x": 44
+              }
+            ],
+            "ordered": true
+          },
+          "expectResult": {
+            "insertedCount": 2,
+            "insertedIds": {
+              "$$unsetOrMatches": {
+                "0": 3,
+                "1": 4
+              }
+            }
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            },
+            {
+              "_id": 4,
+              "x": 44
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "InsertOne fails after connection failure when retryWrites option is false",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.0",
+          "topologies": [
+            "replicaset"
+          ]
+        },
+        {
+          "minServerVersion": "4.1.7",
+          "topologies": [
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client1",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection1",
+          "arguments": {
+            "document": {
+              "_id": 3,
+              "x": 33
+            }
+          },
+          "expectError": {
+            "errorLabelsOmit": [
+              "RetryableWriteError"
+            ]
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "InsertOne fails after multiple retryable writeConcernErrors",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.0",
+          "topologies": [
+            "replicaset"
+          ]
+        },
+        {
+          "minServerVersion": "4.1.7",
+          "topologies": [
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 2
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "writeConcernError": {
+                  "code": 91,
+                  "errmsg": "Replication is being shut down"
+                }
+              }
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "document": {
+              "_id": 3,
+              "x": 33
+            }
+          },
+          "expectError": {
+            "errorLabelsContain": [
+              "RetryableWriteError"
+            ]
+          }
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "coll",
+          "databaseName": "retryable-writes-tests",
+          "documents": [
+            {
+              "_id": 1,
+              "x": 11
+            },
+            {
+              "_id": 2,
+              "x": 22
+            },
+            {
+              "_id": 3,
+              "x": 33
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-retryable-writes.yml b/source/unified-test-format/tests/valid-pass/poc-retryable-writes.yml
new file mode 100644
index 0000000000..0b94fbd803
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-retryable-writes.yml
@@ -0,0 +1,212 @@
+description: "poc-retryable-writes"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "3.6"
+    topologies: [ replicaset ]
+
+createEntities:
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+  - client:
+      id: &client1 client1
+      uriOptions: { retryWrites: false }
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &databaseName retryable-writes-tests
+  - database:
+      id: &database1 database1
+      client: *client1
+      databaseName: *databaseName
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collectionName coll
+  - collection:
+      id: &collection1 collection1
+      database: *database1
+      collectionName: *collectionName
+
+initialData:
+  - collectionName: *collectionName
+    databaseName: *databaseName
+    documents:
+      - { _id: 1, x: 11 }
+      - { _id: 2, x: 22 }
+
+tests:
+  - description: "FindOneAndUpdate is committed on first attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: onPrimaryTransactionalWrite
+            mode: { times: 1 }
+      - name: findOneAndUpdate
+        object: *collection0
+        arguments:
+          filter: { _id: 1 }
+          update: { $inc: { x : 1 } }
+          returnDocument: Before
+        expectResult: { _id: 1, x: 11 }
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 12 }
+          - { _id: 2, x: 22 }
+
+  - description: "FindOneAndUpdate is not committed on first attempt"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: onPrimaryTransactionalWrite
+            mode: { times: 1 }
+            data: { failBeforeCommitExceptionCode: 1 }
+      - name: findOneAndUpdate
+        object: *collection0
+        arguments:
+          filter: { _id: 1 }
+          update: { $inc: { x : 1 } }
+          returnDocument: Before
+        expectResult: { _id: 1, x: 11 }
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 12 }
+          - { _id: 2, x: 22 }
+
+  - description: "FindOneAndUpdate is never committed"
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: onPrimaryTransactionalWrite
+            mode: { times: 2 }
+            data: { failBeforeCommitExceptionCode: 1 }
+      - name: findOneAndUpdate
+        object: *collection0
+        arguments:
+          filter: { _id: 1 }
+          update: { $inc: { x : 1 } }
+          returnDocument: Before
+        expectError: { isError: true }
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+
+  - description: "InsertMany succeeds after PrimarySteppedDown"
+    runOnRequirements: &failCommand_requirements
+      - minServerVersion: "4.0"
+        topologies: [ replicaset ]
+      - minServerVersion: "4.1.7"
+        # Original test uses "sharded", but retryable writes requires a sharded
+        # cluster backed by replica sets
+        topologies: [ sharded-replicaset ]
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ insert ]
+              errorCode: 189 # PrimarySteppedDown
+              errorLabels: [  RetryableWriteError ]
+      - name: insertMany
+        object: *collection0
+        arguments:
+          documents:
+            # Documents are modified from original test for "initialData"
+            - { _id: 3, x: 33 }
+            - { _id: 4, x: 44 }
+          ordered: true
+        expectResult:
+          # insertMany returns a BulkWriteResult, but there is no reason to
+          # assert other fields
+          insertedCount: 2
+          insertedIds: { $$unsetOrMatches: { 0: 3, 1: 4 } }
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+          - { _id: 3, x: 33 }
+          - { _id: 4, x: 44 }
+
+  - description: "InsertOne fails after connection failure when retryWrites option is false"
+    runOnRequirements: *failCommand_requirements
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client1
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+                failCommands: [ insert ]
+                closeConnection: true
+      - name: insertOne
+        object: *collection1
+        arguments:
+          document: { _id: 3, x: 33 }
+        expectError:
+          # If retryWrites is false, the driver should not add the
+          # RetryableWriteError label to the error.
+          errorLabelsOmit: [ RetryableWriteError ]
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+
+  - description: "InsertOne fails after multiple retryable writeConcernErrors"
+    runOnRequirements: *failCommand_requirements
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 2 }
+            data:
+              failCommands: [ insert ]
+              writeConcernError:
+                code: 91 # ShutdownInProgress
+                errmsg: "Replication is being shut down"
+      - name: insertOne
+        object: *collection0
+        arguments:
+          document: { _id: 3, x: 33 }
+        expectError:
+          errorLabelsContain: [ RetryableWriteError ]
+    outcome:
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1, x: 11 }
+          - { _id: 2, x: 22 }
+          - { _id: 3, x: 33 }  # The write was still applied
diff --git a/source/unified-test-format/tests/valid-pass/poc-sessions.json b/source/unified-test-format/tests/valid-pass/poc-sessions.json
new file mode 100644
index 0000000000..75f3489428
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-sessions.json
@@ -0,0 +1,466 @@
+{
+  "description": "poc-sessions",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "3.6.0"
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": false,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "session-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "session-tests",
+      "documents": [
+        {
+          "_id": 1
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "Server supports explicit sessions",
+      "operations": [
+        {
+          "name": "assertSessionNotDirty",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 2
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 2
+              }
+            }
+          }
+        },
+        {
+          "name": "assertSessionNotDirty",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "endSession",
+          "object": "session0"
+        },
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": -1
+            }
+          },
+          "expectResult": []
+        },
+        {
+          "name": "assertSameLsidOnLastTwoCommands",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0"
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 2
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "session-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "test",
+                  "filter": {
+                    "_id": -1
+                  },
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  }
+                },
+                "commandName": "find",
+                "databaseName": "session-tests"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "session-tests",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Server supports implicit sessions",
+      "operations": [
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "document": {
+              "_id": 2
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 2
+              }
+            }
+          }
+        },
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": -1
+            }
+          },
+          "expectResult": []
+        },
+        {
+          "name": "assertSameLsidOnLastTwoCommands",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0"
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 2
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$type": "object"
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "session-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "test",
+                  "filter": {
+                    "_id": -1
+                  },
+                  "lsid": {
+                    "$$type": "object"
+                  }
+                },
+                "commandName": "find",
+                "databaseName": "session-tests"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "session-tests",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "Dirty explicit session is discarded",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.0",
+          "topologies": [
+            "replicaset"
+          ]
+        },
+        {
+          "minServerVersion": "4.1.8",
+          "topologies": [
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "failPoint",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "assertSessionNotDirty",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 2
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 2
+              }
+            }
+          }
+        },
+        {
+          "name": "assertSessionDirty",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 3
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 3
+              }
+            }
+          }
+        },
+        {
+          "name": "assertSessionDirty",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "endSession",
+          "object": "session0"
+        },
+        {
+          "name": "find",
+          "object": "collection0",
+          "arguments": {
+            "filter": {
+              "_id": -1
+            }
+          },
+          "expectResult": []
+        },
+        {
+          "name": "assertDifferentLsidOnLastTwoCommands",
+          "object": "testRunner",
+          "arguments": {
+            "client": "client0"
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 2
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1
+                },
+                "commandName": "insert",
+                "databaseName": "session-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 2
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1
+                },
+                "commandName": "insert",
+                "databaseName": "session-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 3
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 2
+                },
+                "commandName": "insert",
+                "databaseName": "session-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "find": "test",
+                  "filter": {
+                    "_id": -1
+                  },
+                  "lsid": {
+                    "$$type": "object"
+                  }
+                },
+                "commandName": "find",
+                "databaseName": "session-tests"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "session-tests",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            },
+            {
+              "_id": 3
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-sessions.yml b/source/unified-test-format/tests/valid-pass/poc-sessions.yml
new file mode 100644
index 0000000000..cb16657da3
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-sessions.yml
@@ -0,0 +1,214 @@
+description: "poc-sessions"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "3.6.0"
+
+createEntities:
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: false
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name session-tests
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name test
+  - session:
+      id: &session0 session0
+      client: *client0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1 }
+
+tests:
+  - description: "Server supports explicit sessions"
+    operations:
+      - name: assertSessionNotDirty
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 2 }
+        expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 2 } } }
+      - name: assertSessionNotDirty
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: endSession
+        object: *session0
+      - &find_with_implicit_session
+        name: find
+        object: *collection0
+        arguments:
+          filter: { _id: -1 }
+        expectResult: []
+      - name: assertSameLsidOnLastTwoCommands
+        object: testRunner
+        arguments:
+          client: *client0
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collection0Name
+                documents: [ { _id: 2 } ]
+                ordered: true
+                lsid: { $$sessionLsid: *session0 }
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                find: *collection0Name
+                filter: { _id: -1 }
+                lsid: { $$sessionLsid: *session0 }
+              commandName: find
+              databaseName: *database0Name
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
+
+  - description: "Server supports implicit sessions"
+    operations:
+      - name: insertOne
+        object: *collection0
+        arguments:
+          document: { _id: 2 }
+        expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 2 } } }
+      - *find_with_implicit_session
+      - name: assertSameLsidOnLastTwoCommands
+        object: testRunner
+        arguments:
+          client: *client0
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collection0Name
+                documents:
+                  - { _id: 2 }
+                ordered: true
+                # Original test did not include any assertion, but we can use
+                # $$type to expect an arbitrary lsid document
+                lsid: { $$type: object }
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                find: *collection0Name
+                filter: { _id: -1 }
+                lsid: { $$type: object }
+              commandName: find
+              databaseName: *database0Name
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
+
+  - description: "Dirty explicit session is discarded"
+    # Original test specified retryWrites=true, but that is now the default.
+    # Retryable writes will require a sharded-replicaset, though.
+    runOnRequirements:
+      - minServerVersion: "4.0"
+        topologies: [ replicaset ]
+      - minServerVersion: "4.1.8"
+        topologies: [ sharded-replicaset ]
+    operations:
+      - name: failPoint
+        object: testRunner
+        arguments:
+          client: *client0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ insert ]
+              closeConnection: true
+      - name: assertSessionNotDirty
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 2 }
+        expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 2 } } }
+      - name: assertSessionDirty
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 3 }
+        expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 3 } } }
+      - name: assertSessionDirty
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: endSession
+        object: *session0
+      - *find_with_implicit_session
+      - name: assertDifferentLsidOnLastTwoCommands
+        object: testRunner
+        arguments:
+          client: *client0
+    expectEvents:
+      - client: *client0
+        events:
+          # ajv's YAML parser is unable to handle anchors on array elements, so
+          # we define an anchor on the commandStartedEvent object instead
+          - commandStartedEvent: &insert_attempt
+              command:
+                insert: *collection0Name
+                documents: 
+                  - { _id: 2 }
+                ordered: true
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent: *insert_attempt
+          - commandStartedEvent:
+              command:
+                insert: *collection0Name
+                documents: 
+                  - { _id: 3 }
+                ordered: true
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 2
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                find: *collection0Name
+                filter: { _id: -1 }
+                lsid: { $$type: object }
+              commandName: find
+              databaseName: *database0Name
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
+          - { _id: 3 }
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.json b/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.json
new file mode 100644
index 0000000000..820ed65927
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.json
@@ -0,0 +1,505 @@
+{
+  "description": "poc-transactions-convenient-api",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.0",
+      "topologies": [
+        "replicaset"
+      ]
+    },
+    {
+      "minServerVersion": "4.1.8",
+      "topologies": [
+        "sharded-replicaset"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": true,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "client": {
+        "id": "client1",
+        "uriOptions": {
+          "readConcernLevel": "local",
+          "w": 1
+        },
+        "useMultipleMongoses": true,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "transaction-tests"
+      }
+    },
+    {
+      "database": {
+        "id": "database1",
+        "client": "client1",
+        "databaseName": "transaction-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection1",
+        "database": "database1",
+        "collectionName": "test"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0"
+      }
+    },
+    {
+      "session": {
+        "id": "session1",
+        "client": "client1"
+      }
+    },
+    {
+      "session": {
+        "id": "session2",
+        "client": "client0",
+        "sessionOptions": {
+          "defaultTransactionOptions": {
+            "readConcern": {
+              "level": "majority"
+            },
+            "writeConcern": {
+              "w": 1
+            }
+          }
+        }
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "transaction-tests",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "withTransaction and no transaction options set",
+      "operations": [
+        {
+          "name": "withTransaction",
+          "object": "session0",
+          "arguments": {
+            "callback": [
+              {
+                "name": "insertOne",
+                "object": "collection0",
+                "arguments": {
+                  "session": "session0",
+                  "document": {
+                    "_id": 1
+                  }
+                },
+                "expectResult": {
+                  "$$unsetOrMatches": {
+                    "insertedId": {
+                      "$$unsetOrMatches": 1
+                    }
+                  }
+                }
+              }
+            ]
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 1
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "autocommit": false,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "withTransaction inherits transaction options from client",
+      "operations": [
+        {
+          "name": "withTransaction",
+          "object": "session1",
+          "arguments": {
+            "callback": [
+              {
+                "name": "insertOne",
+                "object": "collection1",
+                "arguments": {
+                  "session": "session1",
+                  "document": {
+                    "_id": 1
+                  }
+                },
+                "expectResult": {
+                  "$$unsetOrMatches": {
+                    "insertedId": {
+                      "$$unsetOrMatches": 1
+                    }
+                  }
+                }
+              }
+            ]
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client1",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 1
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session1"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "readConcern": {
+                    "level": "local"
+                  },
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session1"
+                  },
+                  "txnNumber": 1,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "w": 1
+                  },
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "startTransaction": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "withTransaction inherits transaction options from defaultTransactionOptions",
+      "operations": [
+        {
+          "name": "withTransaction",
+          "object": "session2",
+          "arguments": {
+            "callback": [
+              {
+                "name": "insertOne",
+                "object": "collection0",
+                "arguments": {
+                  "session": "session2",
+                  "document": {
+                    "_id": 1
+                  }
+                },
+                "expectResult": {
+                  "$$unsetOrMatches": {
+                    "insertedId": {
+                      "$$unsetOrMatches": 1
+                    }
+                  }
+                }
+              }
+            ]
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 1
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session2"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "readConcern": {
+                    "level": "majority"
+                  },
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session2"
+                  },
+                  "txnNumber": 1,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "w": 1
+                  },
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "startTransaction": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "withTransaction explicit transaction options",
+      "operations": [
+        {
+          "name": "withTransaction",
+          "object": "session0",
+          "arguments": {
+            "callback": [
+              {
+                "name": "insertOne",
+                "object": "collection0",
+                "arguments": {
+                  "session": "session0",
+                  "document": {
+                    "_id": 1
+                  }
+                },
+                "expectResult": {
+                  "$$unsetOrMatches": {
+                    "insertedId": {
+                      "$$unsetOrMatches": 1
+                    }
+                  }
+                }
+              }
+            ],
+            "readConcern": {
+              "level": "majority"
+            },
+            "writeConcern": {
+              "w": 1
+            }
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 1
+                    }
+                  ],
+                  "ordered": true,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "readConcern": {
+                    "level": "majority"
+                  },
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "w": 1
+                  },
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "startTransaction": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.yml b/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.yml
new file mode 100644
index 0000000000..4f981d15dd
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions-convenient-api.yml
@@ -0,0 +1,235 @@
+description: "poc-transactions-convenient-api"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "4.0"
+    topologies: [ replicaset ]
+  - minServerVersion: "4.1.8"
+    topologies: [ sharded-replicaset ]
+
+createEntities:
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: true
+      observeEvents: [ commandStartedEvent ]
+  - client:
+      id: &client1 client1
+      uriOptions:
+        readConcernLevel: local
+        w: 1
+      useMultipleMongoses: true
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &databaseName transaction-tests
+  - database:
+      id: &database1 database1
+      client: *client1
+      databaseName: *databaseName
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collectionName test
+  - collection:
+      id: &collection1 collection1
+      database: *database1
+      collectionName: *collectionName
+  - session:
+      id: &session0 session0
+      client: *client0
+  - session:
+      id: &session1 session1
+      client: *client1
+  - session:
+      id: &session2 session2
+      client: *client0
+      sessionOptions:
+        defaultTransactionOptions:
+          readConcern: { level: majority }
+          writeConcern: { w: 1 }
+
+initialData:
+  - collectionName: *collectionName
+    databaseName: *databaseName
+    documents: []
+
+tests:
+  - description: "withTransaction and no transaction options set"
+    operations:
+      - name: withTransaction
+        object: *session0
+        arguments:
+          callback:
+            - name: insertOne
+              object: *collection0
+              arguments:
+                session: *session0
+                document: { _id: 1 }
+              expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 1 } } }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collectionName
+                documents: [ { _id: 1 } ]
+                ordered: true
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                # omitted fields
+                readConcern: { $$exists: false }
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *databaseName
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                autocommit: false
+                # omitted fields
+                readConcern: { $$exists: false }
+                startTransaction: { $$exists: false }
+                writeConcern: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
+    outcome: &outcome
+      - collectionName: *collectionName
+        databaseName: *databaseName
+        documents:
+          - { _id: 1 }
+
+  - description: "withTransaction inherits transaction options from client"
+    operations:
+      - name: withTransaction
+        object: *session1
+        arguments:
+          callback:
+            - name: insertOne
+              object: *collection1
+              arguments:
+                session: *session1
+                document: { _id: 1 }
+              expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 1 } } }
+    expectEvents:
+      - client: *client1
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collectionName
+                documents: [ { _id: 1 } ]
+                ordered: true
+                lsid: { $$sessionLsid: *session1 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                readConcern: { level: local }
+                # omitted fields
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *databaseName
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session1 }
+                txnNumber: 1
+                autocommit: false
+                writeConcern: { w: 1 }
+                # omitted fields
+                readConcern: { $$exists: false }
+                startTransaction: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
+    outcome: *outcome
+
+  - description: "withTransaction inherits transaction options from defaultTransactionOptions"
+    operations:
+      - name: withTransaction
+        object: *session2
+        arguments:
+          callback:
+            - name: insertOne
+              object: *collection0
+              arguments:
+                session: *session2
+                document: { _id: 1 }
+              expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 1 } } }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collectionName
+                documents: [ { _id: 1 } ]
+                ordered: true
+                lsid: { $$sessionLsid: *session2 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                readConcern: { level: majority }
+                # omitted fields
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *databaseName
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session2 }
+                txnNumber: 1
+                autocommit: false
+                writeConcern: { w: 1 }
+                # omitted fields
+                readConcern: { $$exists: false }
+                startTransaction: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
+    outcome: *outcome
+
+  - description: "withTransaction explicit transaction options"
+    operations:
+      - name: withTransaction
+        object: *session0
+        arguments:
+          callback:
+            - name: insertOne
+              object: *collection0
+              arguments:
+                session: *session0
+                document: { _id: 1 }
+              expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 1 } } }
+          readConcern: { level: majority }
+          writeConcern: { w: 1 }
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                insert: *collectionName
+                documents: [ { _id: 1 } ]
+                ordered: true
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                readConcern: { level: majority }
+                # omitted fields
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *databaseName
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                autocommit: false
+                writeConcern: { w: 1 }
+                # omitted fields
+                readConcern: { $$exists: false }
+                startTransaction: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
+    outcome: *outcome
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.json b/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.json
new file mode 100644
index 0000000000..a0b297d59a
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.json
@@ -0,0 +1,409 @@
+{
+  "description": "poc-transactions-mongos-pin-auto",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.1.8",
+      "topologies": [
+        "sharded-replicaset"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "useMultipleMongoses": true,
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "transaction-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "transaction-tests",
+      "documents": [
+        {
+          "_id": 1
+        },
+        {
+          "_id": 2
+        }
+      ]
+    }
+  ],
+  "tests": [
+    {
+      "description": "remain pinned after non-transient Interrupted error on insertOne",
+      "operations": [
+        {
+          "name": "startTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 3
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 3
+              }
+            }
+          }
+        },
+        {
+          "name": "targetedFailPoint",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "errorCode": 11601
+              }
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 4
+            }
+          },
+          "expectError": {
+            "errorLabelsOmit": [
+              "TransientTransactionError",
+              "UnknownTransactionCommitResult"
+            ],
+            "errorCodeName": "Interrupted"
+          }
+        },
+        {
+          "name": "assertSessionPinned",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "commitTransaction",
+          "object": "session0"
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 3
+                    }
+                  ],
+                  "ordered": true,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 4
+                    }
+                  ],
+                  "ordered": true,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  },
+                  "recoveryToken": {
+                    "$$type": "object"
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            },
+            {
+              "_id": 3
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "unpin after transient error within a transaction",
+      "operations": [
+        {
+          "name": "startTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 3
+            }
+          },
+          "expectResult": {
+            "$$unsetOrMatches": {
+              "insertedId": {
+                "$$unsetOrMatches": 3
+              }
+            }
+          }
+        },
+        {
+          "name": "targetedFailPoint",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0",
+            "failPoint": {
+              "configureFailPoint": "failCommand",
+              "mode": {
+                "times": 1
+              },
+              "data": {
+                "failCommands": [
+                  "insert"
+                ],
+                "closeConnection": true
+              }
+            }
+          }
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": 4
+            }
+          },
+          "expectError": {
+            "errorLabelsContain": [
+              "TransientTransactionError"
+            ],
+            "errorLabelsOmit": [
+              "UnknownTransactionCommitResult"
+            ]
+          }
+        },
+        {
+          "name": "assertSessionUnpinned",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0"
+          }
+        },
+        {
+          "name": "abortTransaction",
+          "object": "session0"
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 3
+                    }
+                  ],
+                  "ordered": true,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "insert": "test",
+                  "documents": [
+                    {
+                      "_id": 4
+                    }
+                  ],
+                  "ordered": true,
+                  "readConcern": {
+                    "$$exists": false
+                  },
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "insert",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "abortTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  },
+                  "recoveryToken": {
+                    "$$type": "object"
+                  }
+                },
+                "commandName": "abortTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ],
+      "outcome": [
+        {
+          "collectionName": "test",
+          "databaseName": "transaction-tests",
+          "documents": [
+            {
+              "_id": 1
+            },
+            {
+              "_id": 2
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.yml b/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.yml
new file mode 100644
index 0000000000..47db7c3188
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions-mongos-pin-auto.yml
@@ -0,0 +1,169 @@
+description: "poc-transactions-mongos-pin-auto"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "4.1.8"
+    topologies: [ sharded-replicaset ]
+
+createEntities:
+  - client:
+      id: &client0 client0
+      useMultipleMongoses: true
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name transaction-tests
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name test
+  - session:
+      id: &session0 session0
+      client: *client0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents:
+      - { _id: 1 }
+      - { _id: 2 }
+
+tests:
+  - description: "remain pinned after non-transient Interrupted error on insertOne"
+    operations:
+      - &startTransaction
+        name: startTransaction
+        object: *session0
+      - &firstInsert
+        name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 3 }
+        expectResult: { $$unsetOrMatches: { insertedId: { $$unsetOrMatches: 3 } } }
+      - name: targetedFailPoint
+        object: testRunner
+        arguments:
+          session: *session0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ insert ]
+              errorCode: 11601 # Interrupted
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 4 }
+        expectError:
+          errorLabelsOmit: [ TransientTransactionError, UnknownTransactionCommitResult ]
+          errorCodeName: Interrupted
+      - name: assertSessionPinned
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: commitTransaction
+        object: *session0
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent: &firstInsertEvent
+              command:
+                insert: *collection0Name
+                documents: [ { _id: 3 } ]
+                ordered: true
+                readConcern: { $$exists: false }
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent: &secondInsertEvent
+              command:
+                insert: *collection0Name
+                documents: [ { _id: 4 } ]
+                ordered: true
+                readConcern: { $$exists: false }
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: { $$exists: false }
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: insert
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: { $$exists: false }
+                autocommit: false
+                writeConcern: { $$exists: false }
+                # Original test expected any value, but we can assert an object
+                recoveryToken: { $$type: object }
+              commandName: commitTransaction
+              databaseName: admin
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
+          - { _id: 3 }
+
+  - description: "unpin after transient error within a transaction"
+    operations:
+      - *startTransaction
+      - *firstInsert
+      - name: targetedFailPoint
+        object: testRunner
+        arguments:
+          session: *session0
+          failPoint:
+            configureFailPoint: failCommand
+            mode: { times: 1 }
+            data:
+              failCommands: [ insert ]
+              closeConnection: true
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: 4 }
+        expectError:
+          errorLabelsContain: [ TransientTransactionError ]
+          errorLabelsOmit: [ UnknownTransactionCommitResult ]
+      - name: assertSessionUnpinned
+        object: testRunner
+        arguments:
+          session: *session0
+      - name: abortTransaction
+        object: *session0
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent: *firstInsertEvent
+          - commandStartedEvent: *secondInsertEvent
+          - commandStartedEvent:
+              command:
+                abortTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: { $$exists: false }
+                autocommit: false
+                writeConcern: { $$exists: false }
+                # Original test expected any value, but we can assert an object
+                recoveryToken: { $$type: object }
+              commandName: abortTransaction
+              databaseName: admin
+    outcome:
+      - collectionName: *collection0Name
+        databaseName: *database0Name
+        documents:
+          - { _id: 1 }
+          - { _id: 2 }
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions.json b/source/unified-test-format/tests/valid-pass/poc-transactions.json
new file mode 100644
index 0000000000..62528f9ce1
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions.json
@@ -0,0 +1,322 @@
+{
+  "description": "poc-transactions",
+  "schemaVersion": "1.0",
+  "runOnRequirements": [
+    {
+      "minServerVersion": "4.0",
+      "topologies": [
+        "replicaset"
+      ]
+    },
+    {
+      "minServerVersion": "4.1.8",
+      "topologies": [
+        "sharded-replicaset"
+      ]
+    }
+  ],
+  "createEntities": [
+    {
+      "client": {
+        "id": "client0",
+        "observeEvents": [
+          "commandStartedEvent"
+        ]
+      }
+    },
+    {
+      "database": {
+        "id": "database0",
+        "client": "client0",
+        "databaseName": "transaction-tests"
+      }
+    },
+    {
+      "collection": {
+        "id": "collection0",
+        "database": "database0",
+        "collectionName": "test"
+      }
+    },
+    {
+      "session": {
+        "id": "session0",
+        "client": "client0"
+      }
+    }
+  ],
+  "initialData": [
+    {
+      "collectionName": "test",
+      "databaseName": "transaction-tests",
+      "documents": []
+    }
+  ],
+  "tests": [
+    {
+      "description": "Client side error in command starting transaction",
+      "operations": [
+        {
+          "name": "startTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "insertOne",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "document": {
+              "_id": {
+                ".": "."
+              }
+            }
+          },
+          "expectError": {
+            "isClientError": true
+          }
+        },
+        {
+          "name": "assertSessionTransactionState",
+          "object": "testRunner",
+          "arguments": {
+            "session": "session0",
+            "state": "starting"
+          }
+        }
+      ]
+    },
+    {
+      "description": "explicitly create collection using create command",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.3.4",
+          "topologies": [
+            "replicaset",
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "dropCollection",
+          "object": "database0",
+          "arguments": {
+            "collection": "test"
+          }
+        },
+        {
+          "name": "startTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "createCollection",
+          "object": "database0",
+          "arguments": {
+            "session": "session0",
+            "collection": "test"
+          }
+        },
+        {
+          "name": "assertCollectionNotExists",
+          "object": "testRunner",
+          "arguments": {
+            "databaseName": "transaction-tests",
+            "collectionName": "test"
+          }
+        },
+        {
+          "name": "commitTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "assertCollectionExists",
+          "object": "testRunner",
+          "arguments": {
+            "databaseName": "transaction-tests",
+            "collectionName": "test"
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "drop": "test",
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "drop",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "create": "test",
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "create",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "description": "create index on a non-existing collection",
+      "runOnRequirements": [
+        {
+          "minServerVersion": "4.3.4",
+          "topologies": [
+            "replicaset",
+            "sharded-replicaset"
+          ]
+        }
+      ],
+      "operations": [
+        {
+          "name": "dropCollection",
+          "object": "database0",
+          "arguments": {
+            "collection": "test"
+          }
+        },
+        {
+          "name": "startTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "createIndex",
+          "object": "collection0",
+          "arguments": {
+            "session": "session0",
+            "name": "x_1",
+            "keys": {
+              "x": 1
+            }
+          }
+        },
+        {
+          "name": "assertIndexNotExists",
+          "object": "testRunner",
+          "arguments": {
+            "databaseName": "transaction-tests",
+            "collectionName": "test",
+            "indexName": "x_1"
+          }
+        },
+        {
+          "name": "commitTransaction",
+          "object": "session0"
+        },
+        {
+          "name": "assertIndexExists",
+          "object": "testRunner",
+          "arguments": {
+            "databaseName": "transaction-tests",
+            "collectionName": "test",
+            "indexName": "x_1"
+          }
+        }
+      ],
+      "expectEvents": [
+        {
+          "client": "client0",
+          "events": [
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "drop": "test",
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "drop",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "createIndexes": "test",
+                  "indexes": [
+                    {
+                      "name": "x_1",
+                      "key": {
+                        "x": 1
+                      }
+                    }
+                  ],
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": true,
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "createIndexes",
+                "databaseName": "transaction-tests"
+              }
+            },
+            {
+              "commandStartedEvent": {
+                "command": {
+                  "commitTransaction": 1,
+                  "lsid": {
+                    "$$sessionLsid": "session0"
+                  },
+                  "txnNumber": 1,
+                  "startTransaction": {
+                    "$$exists": false
+                  },
+                  "autocommit": false,
+                  "writeConcern": {
+                    "$$exists": false
+                  }
+                },
+                "commandName": "commitTransaction",
+                "databaseName": "admin"
+              }
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/source/unified-test-format/tests/valid-pass/poc-transactions.yml b/source/unified-test-format/tests/valid-pass/poc-transactions.yml
new file mode 100644
index 0000000000..5f229e464c
--- /dev/null
+++ b/source/unified-test-format/tests/valid-pass/poc-transactions.yml
@@ -0,0 +1,170 @@
+description: "poc-transactions"
+
+schemaVersion: "1.0"
+
+runOnRequirements:
+  - minServerVersion: "4.0"
+    topologies: [ replicaset ]
+  - minServerVersion: "4.1.8"
+    topologies: [ sharded-replicaset ]
+
+createEntities:
+  - client:
+      id: &client0 client0
+      observeEvents: [ commandStartedEvent ]
+  - database:
+      id: &database0 database0
+      client: *client0
+      databaseName: &database0Name transaction-tests
+  - collection:
+      id: &collection0 collection0
+      database: *database0
+      collectionName: &collection0Name test
+  - session:
+      id: &session0 session0
+      client: *client0
+
+initialData:
+  - collectionName: *collection0Name
+    databaseName: *database0Name
+    documents: []
+
+tests:
+  - description: "Client side error in command starting transaction"
+    operations:
+      - name: startTransaction
+        object: *session0
+      - name: insertOne
+        object: *collection0
+        arguments:
+          session: *session0
+          document: { _id: { .: . } }
+        # Original test only asserted a generic error
+        expectError: { isClientError: true }
+      - name: assertSessionTransactionState
+        object: testRunner
+        arguments:
+          session: *session0
+          state: starting
+
+  - description: "explicitly create collection using create command"
+    runOnRequirements:
+      - minServerVersion: "4.3.4"
+        topologies: [ replicaset, sharded-replicaset ]
+    operations:
+      - name: dropCollection
+        object: *database0
+        arguments:
+          collection: *collection0Name
+      - name: startTransaction
+        object: *session0
+      - name: createCollection
+        object: *database0
+        arguments:
+          session: *session0
+          collection: *collection0Name
+      - name: assertCollectionNotExists
+        object: testRunner
+        arguments:
+          databaseName: *database0Name
+          collectionName: *collection0Name
+      - name: commitTransaction
+        object: *session0
+      - name: assertCollectionExists
+        object: testRunner
+        arguments:
+          databaseName: *database0Name
+          collectionName: *collection0Name
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                drop: *collection0Name
+                writeConcern: { $$exists: false }
+              commandName: drop
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                create: *collection0Name
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: create
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: { $$exists: false }
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
+
+  - description: "create index on a non-existing collection"
+    runOnRequirements:
+      - minServerVersion: "4.3.4"
+        topologies: [ replicaset, sharded-replicaset ]
+    operations:
+      - name: dropCollection
+        object: *database0
+        arguments:
+          collection: *collection0Name
+      - name: startTransaction
+        object: *session0
+      - name: createIndex
+        object: *collection0
+        arguments:
+          session: *session0
+          name: &indexName "x_1"
+          keys: { x: 1 }
+      - name: assertIndexNotExists
+        object: testRunner
+        arguments:
+          databaseName: *database0Name
+          collectionName: *collection0Name
+          indexName: *indexName
+      - name: commitTransaction
+        object: *session0
+      - name: assertIndexExists
+        object: testRunner
+        arguments:
+          databaseName: *database0Name
+          collectionName: *collection0Name
+          indexName: *indexName
+    expectEvents:
+      - client: *client0
+        events:
+          - commandStartedEvent:
+              command:
+                drop: *collection0Name
+                writeConcern: { $$exists: false }
+              commandName: drop
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                createIndexes: *collection0Name
+                indexes:
+                  - name: *indexName
+                    key: { x: 1 }
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: true
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: createIndexes
+              databaseName: *database0Name
+          - commandStartedEvent:
+              command:
+                commitTransaction: 1
+                lsid: { $$sessionLsid: *session0 }
+                txnNumber: 1
+                startTransaction: { $$exists: false }
+                autocommit: false
+                writeConcern: { $$exists: false }
+              commandName: commitTransaction
+              databaseName: admin
diff --git a/source/unified-test-format/unified-test-format.rst b/source/unified-test-format/unified-test-format.rst
new file mode 100644
index 0000000000..b6b1e5e860
--- /dev/null
+++ b/source/unified-test-format/unified-test-format.rst
@@ -0,0 +1,2638 @@
+===================
+Unified Test Format
+===================
+
+:Spec Title: Unified Test Format
+:Spec Version: 1.0.0
+:Author: Jeremy Mikola
+:Advisors: Prashant Mital, Isabel Atkinson, Thomas Reggi
+:Status: Draft
+:Type: Standards
+:Minimum Server Version: N/A
+:Last Modified: 2020-10-08
+
+.. contents::
+
+--------
+
+Abstract
+========
+
+This project defines a unified schema for YAML and JSON specification tests,
+which run operations against a MongoDB deployment. By conforming various spec
+tests to a single schema, drivers can implement a single test runner to execute
+acceptance tests for multiple specifications, thereby reducing maintenance of
+existing specs and implementation time for new specifications.
+
+
+META
+====
+
+The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
+"SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be
+interpreted as described in `RFC 2119 <https://www.ietf.org/rfc/rfc2119.txt>`__.
+
+This document tends to use "SHOULD" more frequently than other specifications,
+but mainly in the context of providing guidance on writing test files. This is
+discussed in more detail in `Design Rationale`_.
+
+
+Goals
+=====
+
+This test format can be used to define tests for the following specifications:
+
+- `Change Streams <../change-streams/change-streams.rst>`__
+- `Command Monitoring <../command-monitoring/command-monitoring.rst>`__
+- `CRUD <../crud/crud.rst>`__
+- `GridFS <../gridfs/gridfs-spec.rst>`__
+- `Retryable Reads <../retryable-reads/retryable-reads.rst>`__
+- `Retryable Writes <../retryable-writes/retryable-writes.rst>`__
+- `Sessions <../sessions/driver-sessions.rst>`__
+- `Transactions <../transactions/transactions.rst>`__
+- `Convenient API for Transactions <../transactions-convenient-api/transactions-convenient-api.rst>`__
+
+This is not an exhaustive list. Specifications that are known to not be
+supported by this format may be discussed under `Future Work`_.
+
+
+Specification
+=============
+
+
+Terms
+-----
+
+Entity
+  Any object or value that is indexed by a unique name and stored in the
+  `Entity Map`_. This will typically be a driver object (e.g. client, session)
+  defined in `createEntities`_ but may also be a
+  `saved operation result <operation_saveResultAsEntity_>`_. A exhaustive list
+  of supported types is presented in `Supported Entity Types`_. Entities are
+  referenced by name throughout the test file (e.g. `Entity Test Operations`_).
+
+Internal MongoClient
+  A MongoClient created specifically for use with internal test operations, such
+  as inserting collection data before a test, performing special assertions
+  during a test, or asserting collection data after a test.
+
+Iterable
+  This term is used by various specifications as the return type for operations
+  that return a sequence of items, which may be iterated. For example, the CRUD
+  spec uses this as the return value for ``find`` and permit API flexibility
+  rather than stipulate that a cursor object be returned directly.
+
+
+Schema Version
+--------------
+
+This specification and the `Test Format`_ follow
+`semantic versioning <https://semver.org/>`__. The version is primarily used to
+validate test files with a `JSON schema <https://json-schema.org/>`__ and also
+allow test runners to determine whether a particular test file is supported.
+
+New tests files SHOULD always be written using the latest major version of this
+specification; however, test files SHOULD be conservative in the minor version
+they specify (as noted in `schemaVersion`_).
+
+
+JSON Schema Validation
+~~~~~~~~~~~~~~~~~~~~~~
+
+Each major version of this specification will have a corresponding JSON schema
+for its most recent minor version (e.g. ``schema-1.1.json``). A JSON schema for
+a particular minor version MUST be capable of validating any and all test files
+in that major version series up to and including the minor version. For example,
+``schema-2.1.json`` should validate test files with `schemaVersion`_ "2.0" and
+"2.1", but would not be expected to validate "1.0", "2.2", or "3.0".
+
+The JSON schema MUST remain consistent with the `Test Format`_ section. If and
+when a new major version is introduced, the `Breaking Changes`_ section MUST be
+updated and any JSON schema(s) for a previous major version(s) MUST remain
+available so that older test files can still be validated.
+
+`Ajv <https://ajv.js.org/>`__ MAY be used to programmatically validate both YAML
+and JSON files using the JSON schema. The JSON schema MUST NOT use syntax that
+is unsupported by this tool, which bears mentioning because there are multiple
+versions of the
+`JSON schema specification <https://json-schema.org/specification.html>`__.
+
+
+Test Runner Support
+~~~~~~~~~~~~~~~~~~~
+
+Each test file defines a `schemaVersion`_, which test runners will use to
+determine compatibility (i.e. whether and how the test file will be
+interpreted). Test files are considered compatible with a test runner if their
+`schemaVersion`_ is less than or equal to a supported version in the test
+runner, given the same major version component. For example:
+
+- A test runner supporting version 1.5.1 could execute test files with versions
+  1.0 and 1.5 but *not* 1.6 and 2.0.
+- A test runner supporting version 2.1 could execute test files with versions
+  2.0 and 2.1 but *not* 1.0 and 1.5.
+- A test runner supporting *both* versions 1.5.1 and 2.0 could execute test
+  files with versions 1.4, 1.5, and 2.0, but *not* 1.6, 2.1, or 3.0.
+- A test runner supporting version 2.0.1 could execute test files with versions
+  2.0 and 2.0.1 but *not* 2.0.2 or 2.1. This example is provided for
+  completeness, but test files SHOULD NOT need to refer to patch versions (as
+  previously mentioned).
+
+Test runners MUST NOT process incompatible files and MUST raise an error if they
+encounter an incompatible file (as discussed in `Executing a Test File`_). Test
+runners MAY support multiple schema versions (as demonstrated in the example
+above).
+
+
+Impact of Spec Changes on Schema Version
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Backwards-breaking changes SHALL warrant a new major version. These changes
+include, but are not limited to:
+
+- Subtractive changes, such as removing a field, operation, or type of supported
+  entity or event
+- Changing an existing field from optional to required
+- Introducing a new, required field in the test format
+- Significant changes to test file execution (not BC)
+
+Backwards-compatible changes SHALL warrant a new minor version. These changes
+include, but are not limited to:
+
+- Additive changes, such as a introducing a new `Special Test Operations`_ or
+  type of supported entity or event
+- Changing an existing field from required to optional
+- Introducing a new, optional field in the test format
+- Minor changes to test file execution (BC)
+
+Small fixes and internal spec changes (e.g. grammar, adding clarifying text to
+the spec) MAY warrant a new patch version; however, patch versions SHOULD NOT
+alter the structure of the test format and thus SHOULD NOT be relevant to test
+files (as noted in `schemaVersion`_).
+
+
+Entity Map
+----------
+
+The entity map indexes arbitrary objects and values by unique names, so that
+they can be referenced from test constructs (e.g.
+`operation.object <operation_object_>`_). To ensure each test is executed in
+isolation, test runners MUST NOT share entity maps between tests. Most entities
+will be driver objects created by the `createEntities`_ directive during test
+setup, but the entity map may also be modified during test execution via the
+`operation.saveResultAsEntity <operation_saveResultAsEntity_>`_ directive.
+
+Test runners MAY choose to implement the entity map in a fashion most suited to
+their language, but implementations MUST enforce both uniqueness of entity names
+and referential integrity when fetching an entity. Test runners MUST raise an
+error if an attempt is made to store an entity with a name that already exists
+in the map and MUST raise an error if an entity is not found for a name or is
+found but has an unexpected type.
+
+Consider the following examples::
+
+    # Error due to a duplicate name (client0 was already defined)
+    createEntities:
+      - client: { id: client0 }
+      - client: { id: client0 }
+
+    # Error due to a missing entity (client1 is undefined)
+    createEntities:
+      - client: { id: client0 }
+      - session: { id: session0, client: client1 }
+
+    # Error due to an unexpected entity type (session instead of client)
+    createEntities:
+      - client: { id: client0 }
+      - session: { id: session0, client: client0 }
+      - session: { id: session1, client: session0 }
+
+
+Supported Entity Types
+~~~~~~~~~~~~~~~~~~~~~~
+
+Test runners MUST support the following types of entities:
+
+- MongoClient. See `entity_client`_ and `Client Operations`_.
+- Database. See `entity_database`_ and `Database Operations`_.
+- Collection. See `entity_collection`_ and `Collection Operations`_
+- ClientSession. See `entity_session`_ and `Session Operations`_.
+- GridFS Bucket. See `entity_bucket`_ and `Bucket Operations`_.
+- ChangeStream. See `ChangeStream Operations`_.
+- All known BSON types and/or equivalent language types for the target driver.
+  For the present version of the spec, the following BSON types are known:
+  0x01-0x13, 0x7F, 0xFF.
+
+  Tests SHOULD NOT utilize deprecated types (e.g. 0x0E: Symbol), since they may
+  not be supported by all drivers and could yield runtime errors (e.g. while
+  loading a test file with an Extended JSON parser).
+
+This is an exhaustive list of supported types for the entity map. Test runners
+MUST raise an error if an attempt is made to store an unsupported type in the
+entity map.
+
+Adding new entity types (including known BSON types) to this list will require
+a minor version bump to the spec and schema version. Removing entity types will
+require a major version bump. See `Impact of Spec Changes on Schema Version`_
+for more information.
+
+
+Test Format
+-----------
+
+Each specification test file can define one or more tests, which inherit some
+top-level configuration (e.g. namespace, initial data). YAML and JSON test files
+are parsed as an object by the test runner. This section defines the top-level
+keys for that object and links to various sub-sections for definitions of
+nested structures (e.g. individual `test`_, `operation`_).
+
+Although test runners are free to process YAML or JSON files, YAML is the
+canonical format for writing tests. YAML files may be converted to JSON using a
+tool such as `js-yaml <https://github.com/nodeca/js-yaml>`__ .
+
+
+Top-level Fields
+~~~~~~~~~~~~~~~~
+
+The top-level fields of a test file are as follows:
+
+- ``description``: Required string. The name of the test file.
+
+  This SHOULD describe the common purpose of tests in this file and MAY refer to
+  the filename (e.g. "updateOne-hint").
+
+.. _schemaVersion:
+
+- ``schemaVersion``: Required string. Version of this specification with which
+  the test file complies.
+
+  Test files SHOULD be conservative when specifying a schema version. For
+  example, if the latest schema version is 1.1 but the test file complies with
+  schema version 1.0, the test file should specify 1.0.
+
+  Test runners will use this to determine compatibility (i.e. whether and how
+  the test file will be interpreted). The format of this string is defined in
+  `Version String`_; however, test files SHOULD NOT need to refer to specific
+  patch versions since patch-level changes SHOULD NOT alter the structure of the
+  test format (as previously noted in `Schema Version`_).
+
+.. _runOnRequirements:
+
+- ``runOnRequirements``: Optional array of one or more `runOnRequirement`_
+  objects. List of server version and/or topology requirements for which the
+  tests in this file can be run. If no requirements are met, the test runner
+  MUST skip this test file.
+
+.. _createEntities:
+
+- ``createEntities``: Optional array of one or more `entity`_ objects. List of
+  entities (e.g. client, collection, session objects) that SHALL be created
+  before each test case is executed.
+
+  Test files SHOULD define entities in dependency order, such that all
+  referenced entities (e.g. client) are defined before any of their dependent
+  entities (e.g. database, session).
+
+.. _initialData:
+
+- ``initialData``: Optional array of one or more `collectionData`_ objects. Data
+  that will exist in collections before each test case is executed.
+
+  Before each test and for each `collectionData`_, the test runner MUST drop the
+  collection and insert the specified documents (if any) using a "majority"
+  write concern. If no documents are specified, the test runner MUST create the
+  collection with a "majority" write concern.
+
+.. _tests:
+
+- ``tests``: Required array of one or more `test`_ objects. List of test cases
+  to be executed independently of each other.
+
+
+runOnRequirement
+~~~~~~~~~~~~~~~~
+
+A combination of server version and/or topology requirements for running the
+test(s).
+
+The format of server version strings is defined in `Version String`_. When
+comparing server version strings, each component SHALL be compared numerically.
+For example, "4.0.10" is greater than "4.0.9" and "3.6" and less than "4.2.0".
+
+The structure of this object is as follows:
+
+- ``minServerVersion``: Optional string. The minimum server version (inclusive)
+  required to successfully run the tests. If this field is omitted, there is no
+  lower bound on the required server version. The format of this string is
+  defined in `Version String`_.
+
+- ``maxServerVersion``: Optional string. The maximum server version (inclusive)
+  against which the tests can be run successfully. If this field is omitted,
+  there is no upper bound on the required server version. The format of this
+  string is defined in `Version String`_.
+
+- ``topologies``: Optional array of one or more strings. Server topologies
+  against which the tests can be run successfully. Valid topologies are
+  "single", "replicaset", "sharded", and "sharded-replicaset" (i.e. sharded
+  cluster backed by replica sets). If this field is omitted, there is no
+  topology requirement for the test.
+
+  When matching a "sharded-replicaset" topology, test runners MUST ensure that
+  all shards are backed by a replica set. The process for doing so is described
+  in `Determining if a Sharded Cluster Uses Replica Sets`_. When matching a
+  "sharded" topology, test runners MUST accept any type of sharded cluster (i.e.
+  "sharded" implies "sharded-replicaset", but not vice versa).
+
+
+entity
+~~~~~~
+
+An entity (e.g. client, collection, session object) that will be created in the
+`Entity Map`_ before each test is executed.
+
+This object MUST contain **exactly one** top-level key that identifies the
+entity type and maps to a nested object, which specifies a unique name for the
+entity (``id`` key) and any other parameters necessary for its construction.
+Tests SHOULD use sequential names based on the entity type (e.g. "session0",
+"session1").
+
+When defining an entity object in YAML, a `node anchor`_ SHOULD be created on
+the entity's ``id`` key. This anchor will allow the unique name to be referenced
+with an `alias node`_ later in the file (e.g. from another entity or
+`operation`_ document) and also leverage YAML's parser for reference validation.
+
+.. _node anchor: https://yaml.org/spec/1.2/spec.html#id2785586
+.. _alias node: https://yaml.org/spec/1.2/spec.html#id2786196
+
+The structure of this object is as follows:
+
+.. _entity_client:
+
+- ``client``: Optional object. Defines a MongoClient object.
+
+  The structure of this object is as follows:
+
+  - ``id``: Required string. Unique name for this entity. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g. ``id: &client0 client0``).
+
+  - ``uriOptions``: Optional object. Additional URI options to apply to the
+    test suite's connection string that is used to create this client. Any keys
+    in this object MUST override conflicting keys in the connection string.
+
+    Documentation for supported options may be found in the
+    `URI Options <../uri-options/uri-options.rst>`__ spec, with one notable
+    exception: if ``readPreferenceTags`` is specified in this object, the key
+    will map to an array of strings, each representing a tag set, since it is
+    not feasible to define multiple ``readPreferenceTags`` keys in the object.
+
+  .. _entity_client_useMultipleMongoses:
+
+  - ``useMultipleMongoses``: Optional boolean. If true and the topology is a
+    sharded cluster, the test runner MUST assert that this MongoClient connects
+    to multiple mongos hosts (e.g. by inspecting the connection string). If
+    false and the topology is a sharded cluster, the test runner MUST ensure
+    that this MongoClient connects to only a single mongos host (e.g. by
+    modifying the connection string).
+
+    If this option is not specified and the topology is a sharded cluster, the
+    test runner MUST NOT enforce any limit on the number of mongos hosts in the
+    connection string and any tests using this client SHOULD NOT depend on a
+    particular number of mongos hosts.
+
+    This option has no effect for non-sharded topologies.
+
+  .. _entity_client_observeEvents:
+
+  - ``observeEvents``: Optional array of one or more strings. Types of events
+    that can be observed for this client. Unspecified event types MUST be
+    ignored by this client's event listeners and SHOULD NOT be included in
+    `test.expectEvents <test_expectEvents_>`_ for this client.
+
+    Test files SHOULD NOT observe events from multiple specs (e.g. command
+    monitoring *and* SDAM events) for a single client. See
+    `Mixing event types in observeEvents and expectEvents`_ for more
+    information.
+
+    Supported types correspond to the top-level keys (strings) documented in
+    `expectedEvent`_ and are as follows:
+
+    - `commandStartedEvent <expectedEvent_commandStartedEvent_>`_
+
+    - `commandSucceededEvent <expectedEvent_commandSucceededEvent_>`_
+
+    - `commandFailedEvent <expectedEvent_commandFailedEvent_>`_
+
+  .. _entity_client_ignoreCommandMonitoringEvents:
+
+  - ``ignoreCommandMonitoringEvents``: Optional array of one or more strings.
+    Command names for which the test runner MUST ignore any observed command
+    monitoring events. The command(s) will be ignored in addition to
+    ``configureFailPoint`` and any commands containing sensitive information
+    (per the
+    `Command Monitoring <../command-monitoring/command-monitoring.rst#security>`__
+    spec).
+
+    Test files SHOULD NOT use this option unless one or more command monitoring
+    events are specified in `observeEvents <entity_client_observeEvents_>`_.
+
+.. _entity_database:
+
+- ``database``: Optional object. Defines a Database object.
+
+  The structure of this object is as follows:
+
+  - ``id``: Required string. Unique name for this entity. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g. ``id: &database0 database0``).
+
+  - ``client``: Required string. Client entity from which this database will be
+    created. The YAML file SHOULD use an `alias node`_ for a client entity's
+    ``id`` field (e.g. ``client: *client0``).
+
+  - ``databaseName``: Required string. Database name. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g.
+    ``databaseName: &database0Name foo``).
+
+  - ``databaseOptions``: Optional `collectionOrDatabaseOptions`_ object.
+
+.. _entity_collection:
+
+- ``collection``: Optional object. Defines a Collection object.
+
+  The structure of this object is as follows:
+
+  - ``id``: Required string. Unique name for this entity. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g.
+    ``id: &collection0 collection0``).
+
+  - ``database``: Required string. Database entity from which this collection
+    will be created. The YAML file SHOULD use an `alias node`_ for a database
+    entity's ``id`` field (e.g. ``database: *database0``).
+
+  - ``collectionName``: Required string. Collection name. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g.
+    ``collectionName: &collection0Name foo``).
+
+  - ``collectionOptions``: Optional `collectionOrDatabaseOptions`_ object.
+
+.. _entity_session:
+
+- ``session``: Optional object. Defines an explicit ClientSession object.
+
+  The structure of this object is as follows:
+
+  - ``id``: Required string. Unique name for this entity. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g. ``id: &session0 session0``).
+
+  - ``client``: Required string. Client entity from which this session will be
+    created. The YAML file SHOULD use an `alias node`_ for a client entity's
+    ``id`` field (e.g. ``client: *client0``).
+
+  - ``sessionOptions``: Optional object. Map of parameters to pass to
+    `MongoClient.startSession <../source/sessions/driver-sessions.rst#startsession>`__
+    when creating the session. Supported options are defined in the following
+    specifications:
+
+    - `Causal Consistency <../causal-consistency/causal-consistency.rst#sessionoptions-changes>`__
+    - `Transactions <../transactions/transactions.rst#sessionoptions-changes>`__
+
+    When specifying TransactionOptions for ``defaultTransactionOptions``, the
+    transaction options MUST remain nested under ``defaultTransactionOptions``
+    and MUST NOT be flattened into ``sessionOptions``.
+
+.. _entity_bucket:
+
+- ``bucket``: Optional object. Defines a Bucket object, as defined in the
+  `GridFS <../gridfs/gridfs-spec.rst>`__ spec.
+
+  The structure of this object is as follows:
+
+  - ``id``: Required string. Unique name for this entity. The YAML file SHOULD
+    define a `node anchor`_ for this field (e.g. ``id: &bucket0 bucket0``).
+
+  - ``database``: Required string. Database entity from which this bucket will
+    be created. The YAML file SHOULD use an `alias node`_ for a database
+    entity's ``id`` field (e.g. ``database: *database0``).
+
+  - ``bucketOptions``: Optional object. Additional options used to construct
+    the bucket object. Supported options are defined in the
+    `GridFS <../source/gridfs/gridfs-spec.rst#configurable-gridfsbucket-class>`__
+    specification. The ``readConcern``, ``readPreference``, and ``writeConcern``
+    options use the same structure as defined in `Common Options`_.
+
+
+collectionData
+~~~~~~~~~~~~~~
+
+List of documents corresponding to the contents of a collection. This structure
+is used by both `initialData`_ and `test.outcome <test_outcome_>`_, which insert
+and read documents, respectively.
+
+The structure of this object is as follows:
+
+- ``collectionName``: Required string. See `commonOptions_collectionName`_.
+
+- ``databaseName``: Required string. See `commonOptions_databaseName`_.
+
+- ``documents``: Required array of objects. List of documents corresponding to
+  the contents of the collection. This list may be empty.
+
+
+test
+~~~~
+
+Test case consisting of a sequence of operations to be executed.
+
+The structure of this object is as follows:
+
+- ``description``: Required string. The name of the test.
+
+  This SHOULD describe the purpose of this test (e.g. "insertOne is retried").
+
+.. _test_runOnRequirements:
+
+- ``runOnRequirements``: Optional array of one or more `runOnRequirement`_
+  objects. List of server version and/or topology requirements for which this
+  test can be run. If specified, these requirements are evaluated independently
+  and in addition to any top-level `runOnRequirements`_. If no requirements in
+  this array are met, the test runner MUST skip this test.
+
+  These requirements SHOULD be more restrictive than those specified in the
+  top-level `runOnRequirements`_ (if any) and SHOULD NOT be more permissive.
+  This is advised because both sets of requirements MUST be satisified in order
+  for a test to be executed and more permissive requirements at the test-level
+  could be taken out of context on their own.
+
+.. _test_skipReason:
+
+- ``skipReason``: Optional string. If set, the test will be skipped. The string
+  SHOULD explain the reason for skipping the test (e.g. JIRA ticket).
+
+.. _test_operations:
+
+- ``operations``: Required array of one or more `operation`_ objects. List of
+  operations to be executed for the test case.
+
+.. _test_expectEvents:
+
+- ``expectEvents``: Optional array of one or more `expectedEventsForClient`_
+  objects. For one or more clients, a list of events that are expected to be
+  observed in a particular order.
+
+  If a driver only supports configuring event listeners globally (for all
+  clients), the test runner SHOULD associate each observed event with a client
+  in order to perform these assertions.
+
+  Test files SHOULD NOT expect events from multiple specs (e.g. command
+  monitoring *and* SDAM events) for a single client. See
+  `Mixing event types in observeEvents and expectEvents`_ for more
+  information.
+
+.. _test_outcome:
+
+- ``outcome``: Optional array of one or more `collectionData`_ objects. Data
+  that is expected to exist in collections after each test case is executed.
+
+  The list of documents herein SHOULD be sorted ascendingly by the ``_id`` field
+  to allow for deterministic comparisons. The procedure for asserting collection
+  contents is discussed in `Executing a Test`_.
+
+
+operation
+~~~~~~~~~
+
+An operation to be executed as part of the test.
+
+The structure of this object is as follows:
+
+.. _operation_name:
+
+- ``name``: Required string. Name of the operation (e.g. method) to perform on
+  the object.
+
+.. _operation_object:
+
+- ``object``: Required string. Name of the object on which to perform the
+  operation. This SHOULD correspond to either an `entity`_ name (for
+  `Entity Test Operations`_) or "testRunner" (for `Special Test Operations`_).
+  If the object is an entity, The YAML file SHOULD use an `alias node`_ for its
+  ``id`` field (e.g. ``object: *collection0``).
+
+.. _operation_arguments:
+
+- ``arguments``: Optional object. Map of parameter names and values for the
+  operation. The structure of this object will vary based on the operation.
+  See `Entity Test Operations`_ and `Special Test Operations`_.
+
+  The ``session`` parameter is handled specially (see `commonOptions_session`_).
+
+.. _operation_expectError:
+
+- ``expectError``: Optional `expectedError`_ object. One or more assertions for
+  an error expected to be raised by the operation.
+
+  This field is mutually exclusive with
+  `expectResult <operation_expectResult_>`_ and
+  `saveResultAsEntity <operation_saveResultAsEntity_>`_.
+
+  This field SHOULD NOT be used for `Special Test Operations`_ (i.e.
+  ``object: testRunner``).
+
+.. _operation_expectResult:
+
+- ``expectResult``: Optional mixed type. A value corresponding to the expected
+  result of the operation. This field may be a scalar value, a single document,
+  or an array of values. Test runners MUST follow the rules in
+  `Evaluating Matches`_ when processing this assertion.
+
+  This field is mutually exclusive with `expectError <operation_expectError_>`_.
+
+  This field SHOULD NOT be used for `Special Test Operations`_ (i.e.
+  ``object: testRunner``).
+
+.. _operation_saveResultAsEntity:
+
+- ``saveResultAsEntity``: Optional string. If specified, the actual result
+  returned by the operation (if any) will be saved with this name in the
+  `Entity Map`_.  The test runner MUST raise an error if the name is already in
+  use or if the result does not comply with `Supported Entity Types`_.
+
+  This field is mutually exclusive with `expectError <operation_expectError_>`_.
+
+  This field SHOULD NOT be used for `Special Test Operations`_ (i.e.
+  ``object: testRunner``).
+
+
+expectedError
+~~~~~~~~~~~~~
+
+One or more assertions for an error/exception, which is expected to be raised by
+an executed operation. At least one key is required in this object.
+
+The structure of this object is as follows:
+
+- ``isError``: Optional boolean. If true, the test runner MUST assert that an
+  error was raised. This is primarily used when no other error assertions apply
+  but the test still needs to assert an expected error. Test files MUST NOT
+  specify false, as `expectedError`_ is only applicable when an operation is
+  expected to raise an error.
+
+- ``isClientError``: Optional boolean. If true, the test runner MUST assert that
+  the error originates from the client (i.e. it is not derived from a server
+  response). If false, the test runner MUST assert that the error does not
+  originate from the client.
+
+  Client errors include, but are not limited to: parameter validation errors
+  before a command is sent to the server; network errors.
+
+- ``errorContains``: Optional string. A substring of the expected error message
+  (e.g. "errmsg" field in a server error document). The test runner MUST assert
+  that the error message contains this string using a case-insensitive match.
+
+  See `bulkWrite`_ for special considerations for BulkWriteExceptions.
+
+- ``errorCode``: Optional integer. The expected "code" field in the
+  server-generated error response. The test runner MUST assert that the error
+  includes a server-generated response whose "code" field equals this value.
+  In the interest of readability, YAML files SHOULD use a comment to note the
+  corresponding code name (e.g. ``errorCode: 26 # NamespaceNotFound``).
+
+  Server error codes are defined in
+  `error_codes.yml <https://github.com/mongodb/mongo/blob/master/src/mongo/base/error_codes.yml>`__.
+
+  Test files SHOULD NOT assert error codes for client errors, as specifications
+  do not define standardized codes for client errors.
+
+- ``errorCodeName``: Optional string. The expected "codeName" field in the
+  server-generated error response. The test runner MUST assert that the error
+  includes a server-generated response whose "codeName" field equals this value
+  using a case-insensitive comparison.
+
+  See `bulkWrite`_ for special considerations for BulkWriteExceptions.
+
+  Server error codes are defined in
+  `error_codes.yml <https://github.com/mongodb/mongo/blob/master/src/mongo/base/error_codes.yml>`__.
+
+  Test files SHOULD NOT assert error codes for client errors, as specifications
+  do not define standardized codes for client errors.
+
+- ``errorLabelsContain``: Optional array of one or more strings. A list of error
+  label strings that the error is expected to have. The test runner MUST assert
+  that the error contains all of the specified labels (e.g. using the
+  ``hasErrorLabel`` method).
+
+- ``errorLabelsOmit``: Optional array of one or more strings. A list of error
+  label strings that the error is expected not to have. The test runner MUST
+  assert that the error does not contain any of the specified labels (e.g. using
+  the ``hasErrorLabel`` method).
+
+.. _expectedError_expectResult:
+
+- ``expectResult``: Optional mixed type. This field follows the same rules as
+  `operation.expectResult <operation_expectResult_>`_ and is only used in cases
+  where the error includes a result (e.g. `bulkWrite`_). If specified, the test
+  runner MUST assert that the error includes a result and that it matches this
+  value.
+
+
+expectedEventsForClient
+~~~~~~~~~~~~~~~~~~~~~~~
+
+A list of events that are expected to be observed (in that order) for a client
+while executing `operations <test_operations_>`_.
+
+The structure of each object is as follows:
+
+- ``client``: Required string. Client entity on which the events are expected
+  to be observed. See `commonOptions_client`_.
+
+- ``events``: Required array of `expectedEvent`_ objects. List of events, which
+  are expected to be observed (in this order) on the corresponding client while
+  executing `operations`_. If the array is empty, the test runner MUST assert
+  that no events were observed on the client (excluding ignored events).
+
+
+expectedEvent
+~~~~~~~~~~~~~
+
+An event (e.g. APM), which is expected to be observed while executing the test's
+operations.
+
+This object MUST contain **exactly one** top-level key that identifies the
+event type and maps to a nested object, which contains one or more assertions
+for the event's properties.
+
+Some event properties are omitted in the following structures because they
+cannot be reliably tested. Taking command monitoring events as an example,
+``requestId`` and ``operationId`` are nondeterministic and types for
+``connectionId`` and ``failure`` can vary by implementation.
+
+The structure of this object is as follows:
+
+.. _expectedEvent_commandStartedEvent:
+
+- ``commandStartedEvent``: Optional object. Assertions for one or more
+  `CommandStartedEvent <../command-monitoring/command-monitoring.rst#api>`__
+  fields.
+
+  The structure of this object is as follows:
+
+  - ``command``: Optional document. A value corresponding to the expected
+    command document. Test runners MUST follow the rules in
+    `Evaluating Matches`_ when processing this assertion.
+
+  - ``commandName``: Optional string. Test runners MUST assert that the command
+    name matches this value.
+
+  - ``databaseName``: Optional string. Test runners MUST assert that the
+    database name matches this value. The YAML file SHOULD use an `alias node`_
+    for this value (e.g. ``databaseName: *database0Name``).
+
+.. _expectedEvent_commandSucceededEvent:
+
+- ``commandSucceededEvent``: Optional object. Assertions for one or more
+  `CommandSucceededEvent <../command-monitoring/command-monitoring.rst#api>`__
+  fields.
+
+  The structure of this object is as follows:
+
+  - ``reply``: Optional document. A value corresponding to the expected
+    reply document. Test runners MUST follow the rules in `Evaluating Matches`_
+    when processing this assertion.
+
+  - ``commandName``: Optional string. Test runners MUST assert that the command
+    name matches this value.
+
+.. _expectedEvent_commandFailedEvent:
+
+- ``commandFailedEvent``: Optional object. Assertions for one or more
+  `CommandFailedEvent <../command-monitoring/command-monitoring.rst#api>`__
+  fields.
+
+  The structure of this object is as follows:
+
+  - ``commandName``: Optional string. Test runners MUST assert that the command
+    name matches this value.
+
+
+collectionOrDatabaseOptions
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Map of parameters used to construct a collection or database object.
+
+The structure of this object is as follows:
+
+  - ``readConcern``: Optional object. See `commonOptions_readConcern`_.
+
+  - ``readPreference``: Optional object. See `commonOptions_readPreference`_.
+
+  - ``writeConcern``: Optional object. See `commonOptions_writeConcern`_.
+
+
+Common Options
+--------------
+
+This section defines the structure of common options that are referenced from
+various contexts in the test format. Comprehensive documentation for some of
+these types and their parameters may be found in the following specifications:
+
+- `Read and Write Concern <../read-write-concern/read-write-concern.rst>`__.
+- `Server Selection: Read Preference <../server-selection/server-selection.rst#read-preference>`__.
+
+The structure of these common options is as follows:
+
+.. _commonOptions_collectionName:
+
+- ``collectionName``: String. Collection name. The YAML file SHOULD use an
+  `alias node`_ for a collection entity's ``collectionName`` field (e.g.
+  ``collectionName: *collection0Name``).
+
+.. _commonOptions_databaseName:
+
+- ``databaseName``: String. Database name. The YAML file SHOULD use an
+  `alias node`_ for a database entity's ``databaseName`` field (e.g.
+  ``databaseName: *database0Name``).
+
+.. _commonOptions_readConcern:
+
+- ``readConcern``: Object. Map of parameters to construct a read concern.
+
+  The structure of this object is as follows:
+
+  - ``level``: Required string.
+
+.. _commonOptions_readPreference:
+
+- ``readPreference``: Object. Map of parameters to construct a read
+  preference.
+
+  The structure of this object is as follows:
+
+  - ``mode``: Required string.
+
+  - ``tagSets``: Optional array of objects.
+
+  - ``maxStalenessSeconds``: Optional integer.
+
+  - ``hedge``: Optional object.
+
+.. _commonOptions_client:
+
+- ``client``: String. Client entity name, which the test runner MUST resolve
+  to a MongoClient object. The YAML file SHOULD use an `alias node`_ for a
+  client entity's ``id`` field (e.g. ``client: *client0``).
+
+.. _commonOptions_session:
+
+- ``session``: String. Session entity name, which the test runner MUST resolve
+  to a ClientSession object. The YAML file SHOULD use an `alias node`_ for a
+  session entity's ``id`` field (e.g. ``session: *session0``).
+
+.. _commonOptions_writeConcern:
+
+- ``writeConcern``: Object. Map of parameters to construct a write concern.
+
+  The structure of this object is as follows:
+
+  - ``journal``: Optional boolean.
+
+  - ``w``: Optional integer or string.
+
+  - ``wtimeoutMS``: Optional integer.
+
+
+Version String
+--------------
+
+Version strings, which are used for `schemaVersion`_ and `runOnRequirement`_,
+MUST conform to one of the following formats, where each component is a
+non-negative integer:
+
+- ``<major>.<minor>.<patch>``
+- ``<major>.<minor>`` (``<patch>`` is assumed to be zero)
+- ``<major>`` (``<minor>`` and ``<patch>`` are assumed to be zero)
+
+
+Entity Test Operations
+----------------------
+
+Entity operations correspond to an API method on a driver object. If
+`operation.object <operation_object_>`_ refers to an `entity`_ name (e.g.
+"collection0") then `operation.name <operation_name_>`_ is expected to reference
+an API method on that class.
+
+Test files SHALL use camelCase when referring to API methods and parameters,
+even if the defining specifications use other forms (e.g. snake_case in GridFS).
+
+This spec does not provide exhaustive documentation for all possible API methods
+that may appear in a test; however, the following sections discuss all supported
+entities and their operations in some level of detail. Special handling for
+certain operations is also discussed as needed.
+
+
+Expressing Required and Optional Parameters
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Some specifications group optional parameters for API methods under an
+``options`` parameter (e.g. ``options: Optional<UpdateOptions>`` in the CRUD
+spec); however, driver APIs vary in how they accept options (e.g. Python's
+keyword/named arguments, ``session`` as either an option or required parameter
+depending on whether a language supports method overloading). Therefore, test
+files SHALL declare all required and optional parameters for an API method
+directly within `operation.arguments <operation_arguments_>`_ (e.g. ``upsert``
+for ``updateOne`` is *not* nested under an ``options`` key).
+
+
+Special Handling for Arguments
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If ``session`` is specified in `operation.arguments`_, it is defined according
+to `commonOptions_session`_. Test runners MUST resolve the ``session`` argument
+to `session <entity_session_>`_ entity *before* passing it as a parameter to any
+API method.
+
+If ``readConcern``, ``readPreference``, or ``writeConcern`` are specified in
+`operation.arguments`_, test runners MUST interpret them according to the
+corresponding definition in `Common Options`_ and MUST convert the value into
+the appropriate object *before* passing it as a parameter to any API method.
+
+
+Converting Returned Model Objects to Documents
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For operations that return a model object (e.g. ``BulkWriteResult`` for
+``bulkWrite``), the test runner MUST convert the model object to a document when
+evaluating `expectResult <operation_expectResult_>`_ or
+`saveResultAsEntity <operation_saveResultAsEntity_>`_. Similarly, for operations
+that may return iterables of model objects (e.g. ``DatabaseInfo`` for
+``listDatabases``), the test runner MUST convert the iterable to an array of
+documents when evaluating `expectResult`_ or `saveResultAsEntity`_.
+
+
+Iterating Returned Iterables
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Unless otherwise stated by an operation below, test runners MUST fully iterate
+any iterable returned by an operation as part of that operation's execution.
+This is necessary to ensure consistent behavior among drivers, as discussed in
+`aggregate`_ and `find`_, and also ensures that error and event assertions can
+be evaluated consistently.
+
+
+Client Operations
+-----------------
+
+These operations and their arguments may be documented in the following
+specifications:
+
+- `Change Streams <../change-streams/change-streams.rst>`__
+- `Enumerating Databases <../enumerate-databases.rst>`__
+
+Client operations that require special handling or are not documented by an
+existing specification are described below.
+
+
+.. _client_createChangeStream:
+
+createChangeStream
+~~~~~~~~~~~~~~~~~~
+
+Creates a cluster-level change stream and ensures that the server-side cursor
+has been created.
+
+This operation proxies the client's ``watch`` method and supports the same
+arguments and options. Test files SHOULD NOT use the client's ``watch``
+operation directly for reasons discussed in `ChangeStream Operations`_. Test
+runners MUST ensure that the server-side cursor is created (i.e. ``aggregate``
+is executed) as part of this operation and before the resulting change stream
+might be saved with
+`operation.saveResultAsEntity <operation_saveResultAsEntity_>`_.
+
+Test runners MUST NOT iterate the change stream when executing this operation
+and test files SHOULD NOT specify
+`operation.expectResult <operation_expectResult_>`_ for this operation.
+
+
+watch
+~~~~~
+
+This operation SHOULD NOT be used in test files. See
+`client_createChangeStream`_.
+
+
+Database Operations
+-------------------
+
+These operations and their arguments may be documented in the following
+specifications:
+
+- `Change Streams <../change-streams/change-streams.rst>`__
+- `CRUD <../crud/crud.rst>`__
+- `Enumerating Collections <../enumerate-collections.rst>`__
+
+Database operations that require special handling or are not documented by an
+existing specification are described below.
+
+
+.. _database_createChangeStream:
+
+createChangeStream
+~~~~~~~~~~~~~~~~~~
+
+Creates a database-level change stream and ensures that the server-side cursor
+has been created.
+
+This operation proxies the database's ``watch`` method and supports the same
+arguments and options. Test files SHOULD NOT use the database's ``watch``
+operation directly for reasons discussed in `ChangeStream Operations`_. Test
+runners MUST ensure that the server-side cursor is created (i.e. ``aggregate``
+is executed) as part of this operation and before the resulting change stream
+might be saved with
+`operation.saveResultAsEntity <operation_saveResultAsEntity_>`_.
+
+Test runners MUST NOT iterate the change stream when executing this operation
+and test files SHOULD NOT specify
+`operation.expectResult <operation_expectResult_>`_ for this operation.
+
+
+runCommand
+~~~~~~~~~~
+
+Generic command runner.
+
+This method does not inherit a read concern or write concern (per the
+`Read and Write Concern <../read-write-concern/read-write-concern.rst#generic-command-method>`__
+spec), nor does it inherit a read preference (per the
+`Server Selection <../server-selection/server-selection.rst#use-of-read-preferences-with-commands>`__
+spec); however, they may be specified as arguments.
+
+The following arguments are supported:
+
+- ``command``: Required document. The command to be executed.
+
+- ``commandName``: Required string. The name of the command to run. This is used
+  by languages that are unable preserve the order of keys in the ``command``
+  argument when parsing YAML/JSON.
+
+- ``readConcern``: Optional object. See `commonOptions_readConcern`_.
+
+- ``readPreference``: Optional object. See `commonOptions_readPreference`_.
+
+- ``session``: Optional string. See `commonOptions_session`_.
+
+- ``writeConcern``: Optional object. See `commonOptions_writeConcern`_.
+
+
+watch
+~~~~~
+
+This operation SHOULD NOT be used in test files. See
+`database_createChangeStream`_.
+
+
+Collection Operations
+---------------------
+
+These operations and their arguments may be documented in the following
+specifications:
+
+- `Change Streams <../change-streams/change-streams.rst>`__
+- `CRUD <../crud/crud.rst>`__
+- `Enumerating Indexes <../enumerate-indexes.rst>`__
+- `Index Management <../index-management.rst>`__
+
+Collection operations that require special handling or are not documented by an
+existing specification are described below.
+
+
+aggregate
+~~~~~~~~~
+
+When executing an ``aggregate`` operation, the test runner MUST fully iterate
+the result. This will ensure consistent behavior between drivers that eagerly
+create a server-side cursor and those that do so lazily when iteration begins.
+
+
+bulkWrite
+~~~~~~~~~
+
+The ``requests`` parameter for ``bulkWrite`` is documented as a list of
+WriteModel interfaces. Each WriteModel implementation (e.g. InsertOneModel)
+provides important context to the method, but that type information is not
+easily expressed in YAML and JSON. To account for this, test files MUST nest
+each WriteModel object in a single-key object, where the key identifies the
+request type (e.g. "insertOne") and its value is an object expressing the
+parameters, as in the following example::
+
+    arguments:
+      requests:
+        - insertOne:
+            document: { _id: 1, x: 1 }
+        - replaceOne:
+            filter: { _id: 2 }
+            replacement: { x: 2 }
+            upsert: true
+        - updateOne:
+            filter: { _id: 3 }
+            update: { $set: { x: 3 } }
+            upsert: true
+        - updateMany:
+            filter: { }
+            update: { $inc: { x: 1 } }
+        - deleteOne:
+            filter: { x: 2 }
+        - deleteMany:
+            filter: { x: { $gt: 2 } }
+      ordered: true
+
+Because the ``insertedIds`` field of BulkWriteResult is optional for drivers to
+implement, assertions for that field SHOULD utilize the `$$unsetOrMatches`_
+operator.
+
+While operations typically raise an error *or* return a result, the
+``bulkWrite`` operation is unique in that it may report both via the
+``writeResult`` property of a BulkWriteException. In this case, the intermediary
+write result may be matched with `expectedError_expectResult`_. Because
+``writeResult`` is optional for drivers to implement, such assertions SHOULD
+utilize the `$$unsetOrMatches`_ operator.
+
+Additionally, BulkWriteException is unique in that it aggregates one or more
+server errors in its ``writeConcernError`` and ``writeErrors`` properties.
+When test runners evaluate `expectedError`_ assertions for ``errorContains`` and
+``errorCodeName``, they MUST examine the aggregated errors and consider any
+match therein to satisfy the assertion(s). Drivers that concatenate all write
+and write concern error messages into the BulkWriteException message MAY
+optimize the check for ``errorContains`` by examining the concatenated message.
+Drivers that expose ``code`` but not ``codeName`` through BulkWriteException MAY
+translate the expected code name to a number (see:
+`error_codes.yml <https://github.com/mongodb/mongo/blob/master/src/mongo/base/error_codes.yml>`__)
+and compare with ``code`` instead, but MUST raise an error if the comparison
+cannot be attempted (e.g. ``code`` is also not available, translation fails).
+
+
+.. _collection_createChangeStream:
+
+createChangeStream
+~~~~~~~~~~~~~~~~~~
+
+Creates a collection-level change stream and ensures that the server-side cursor
+has been created.
+
+This operation proxies the collection's ``watch`` method and supports the same
+arguments and options. Test files SHOULD NOT use the collection's ``watch``
+operation directly for reasons discussed in `ChangeStream Operations`_. Test
+runners MUST ensure that the server-side cursor is created (i.e. ``aggregate``
+is executed) as part of this operation and before the resulting change stream
+might be saved with
+`operation.saveResultAsEntity <operation_saveResultAsEntity_>`_.
+
+Test runners MUST NOT iterate the change stream when executing this operation
+and test files SHOULD NOT specify
+`operation.expectResult <operation_expectResult_>`_ for this operation.
+
+
+find
+~~~~
+
+When executing a ``find`` operation, the test runner MUST fully iterate the
+result. This will ensure consistent behavior between drivers that eagerly create
+a server-side cursor and those that do so lazily when iteration begins.
+
+
+findOneAndReplace and findOneAndUpdate
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``returnDocument`` option for ``findOneAndReplace`` and ``findOneAndUpdate``
+is documented as an enum with possible values "Before" and "After". Test files
+SHOULD express ``returnDocument`` as a string and test runners MUST raise an
+error if its value does not case-insensitively match either enum value.
+
+
+insertMany
+~~~~~~~~~~
+
+The CRUD spec documents ``insertMany`` as returning a BulkWriteResult. Because
+the ``insertedIds`` field of BulkWriteResult is optional for drivers to
+implement, assertions for that field SHOULD utilize the `$$unsetOrMatches`_
+operator.
+
+
+insertOne
+~~~~~~~~~
+
+The CRUD spec documents ``insertOne`` as returning an InsertOneResult; however,
+because all fields InsertOneResult are optional drivers are permitted to forgo
+it entirely and have ``insertOne`` return nothing (i.e. void method). Tests
+asserting InsertOneResult SHOULD utilize the `$$unsetOrMatches`_ operator for
+*both* the result object and any optional fields within, as in the following
+examples::
+
+    - name: insertOne
+      object: *collection0
+      arguments:
+        document: { _id: 2 }
+      expectResult:
+        $$unsetOrMatches:
+          insertedId: { $$unsetOrMatches: 2 }
+
+
+watch
+~~~~~
+
+This operation SHOULD NOT be used in test files. See
+`collection_createChangeStream`_.
+
+
+Session Operations
+------------------
+
+These operations and their arguments may be documented in the following
+specifications:
+
+- `Convenient API for Transactions <../transactions-convenient-api/transactions-convenient-api.rst>`__
+- `Driver Sessions <../sessions/driver-sessions.rst>`__
+
+Session operations that require special handling or are not documented by an
+existing specification are described below.
+
+
+withTransaction
+~~~~~~~~~~~~~~~
+
+The ``withTransaction`` operation's ``callback`` parameter is a function and not
+easily expressed in YAML/JSON. For ease of testing, this parameter is expressed
+as an array of `operation`_ objects (analogous to
+`test.operations <test_operations>`_). Test runners MUST evaluate error and
+result assertions when executing these operations in the callback.
+
+
+Bucket Operations
+-----------------
+
+These operations and their arguments may be documented in the following
+specifications:
+
+- `GridFS <../gridfs/gridfs-spec.rst>`__
+
+Bucket operations that require special handling or are not documented by an
+existing specification are described below.
+
+
+.. _download:
+.. _downloadByName:
+
+download and downloadByName
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations proxy the bucket's ``openDownloadStream`` and
+``openDownloadStreamByName`` methods and support the same parameters and
+options, but return a string containing the stream's contents instead of the
+stream itself. Test runners MUST fully read the stream to yield the returned
+string. This is also necessary to ensure that any expected errors are raised
+(e.g. missing chunks). Test files SHOULD use `$$matchesHexBytes`_ in
+`expectResult <operation_expectResult_>`_ to assert the contents of the returned
+string.
+
+
+downloadToStream and downloadToStreamByName
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations SHOULD NOT be used in test files. See
+`IO operations for GridFS streams`_ in `Future Work`_.
+
+
+openDownloadStream and openDownloadStreamByName
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations SHOULD NOT be used in test files. See
+`download and downloadByName`_.
+
+
+.. _openUploadStream:
+.. _openUploadStreamWithId:
+
+openUploadStream and openUploadStreamWithId
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations SHOULD NOT be used in test files. See
+`IO operations for GridFS streams`_ in `Future Work`_. 
+
+
+.. _upload:
+.. _uploadWithId:
+
+upload and uploadWithId
+~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations proxy the bucket's ``uploadFromStream`` and
+``uploadFromStreamWithId`` methods and support the same parameters and options
+with one exception: the ``source`` parameter is an object specifying hex bytes
+from which test runners MUST construct a readable stream for the underlying
+methods. The structure of ``source`` is as follows::
+
+    { $$hexBytes: <string> }
+
+The string MUST contain an even number of hexademical characters
+(case-insensitive) and MAY be empty. The test runner MUST raise an error if the
+structure of ``source`` or its string is malformed. The test runner MUST convert
+the string to a byte sequence denoting the stream's readable data (if any). For
+example, "12ab" would denote a stream with two bytes: "0x12" and "0xab".
+
+
+
+uploadFromStream and uploadFromStreamWithId
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+These operations SHOULD NOT be used in test files. See
+`upload and uploadWithId`_.
+
+
+ChangeStream Operations
+-----------------------
+
+Change stream entities are special in that they are not defined in
+`createEntities`_ but are instead created by using
+`operation.saveResultAsEntity <operation_saveResultAsEntity_>`_ with a
+`client_createChangeStream`_, `database_createChangeStream`_, or
+`collection_createChangeStream`_ operation.
+
+Test files SHOULD NOT use a ``watch`` operation to create a change stream, as
+the implementation of that method may vary among drivers. For example, some
+implementations of ``watch`` immediately execute ``aggregate`` and construct the
+server-side cursor, while others may defer ``aggregate`` until the change stream
+object is iterated.
+
+The `Change Streams <../change-streams/change-streams.rst>`__ spec does not
+define a consistent API for the ChangeStream class, since the mechanisms for
+iteration and capturing a resume token may differ between synchronous and
+asynchronous drivers. To account for this, this section explicitly defines the
+supported operations for change stream entities.
+
+
+iterateUntilDocumentOrError
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Iterates the change stream until either a single document is returned or an
+error is raised. This operation takes no arguments. If
+`expectResult <operation_expectResult_>`_ is specified, it SHOULD be a single
+document.
+
+`Iterating the Change Stream <../change-streams/tests#iterating-the-change-stream>`__
+in the change stream spec cautions drivers that implement a blocking mode of
+iteration (e.g. asynchronous drivers) not to iterate the change stream
+unnecessarily, as doing so could cause the test runner to block indefinitely.
+This should not be a concern for ``iterateUntilDocumentOrError`` as iteration
+only continues until either a document or error is encountered.
+
+Test runners MUST ensure that this operation will not inadvertently skip the
+first document in a change stream. Albeit rare, this could happen if
+``iterateUntilDocumentOrError`` were to blindly invoke ``next`` (or equivalent)
+on a change stream in a driver where newly created change streams are already
+positioned at their first element and the change stream cursor had a non-empty
+``firstBatch`` (i.e. ``resumeAfter`` or ``startAfter`` used). Alternatively,
+some drivers may use a different iterator method for advancing a change stream
+to its first position (e.g. ``rewind`` in PHP).
+
+
+Special Test Operations
+-----------------------
+
+Certain operations do not correspond to API methods but instead represent
+special test operations (e.g. assertions). These operations are distinguished by
+`operation.object <operation_object_>`_ having a value of "testRunner". The
+`operation.name <operation_name_>`_ field will correspond to an operation
+defined below.
+
+Special test operations return no result and are always expected to succeed.
+These operations SHOULD NOT be combined with
+`expectError <operation_expectError_>`_,
+`expectResult <operation_expectResult_>`_, or
+`saveResultAsEntity <operation_saveResultAsEntity_>`_.
+
+
+failPoint
+~~~~~~~~~
+
+The ``failPoint`` operation instructs the test runner to configure a fail point
+using a "primary" read preference using the specified client entity (fail points
+are not configured using the internal MongoClient).
+
+The following arguments are supported:
+
+- ``failPoint``: Required document. The ``configureFailPoint`` command to be
+  executed.
+
+- ``client``: Required string. See `commonOptions_client`_.
+
+  The client entity SHOULD specify false for
+  `useMultipleMongoses <entity_client_useMultipleMongoses_>`_ if this operation
+  could be executed on a sharded topology (according to `runOnRequirements`_ or
+  `test.runOnRequirements <test_runOnRequirements_>`_). This is advised because
+  server selection rules for mongos could lead to unpredictable behavior if
+  different servers were selected for configuring the fail point and executing
+  subsequent operations.
+
+When executing this operation, the test runner MUST keep a record of the fail
+point so that it can be disabled after the test. The test runner MUST also
+ensure that the ``configureFailPoint`` command is excluded from the list of
+observed command monitoring events for this client (if applicable).
+
+An example of this operation follows::
+
+    # Enable the fail point on the server selected with a primary read preference
+    - name: failPoint
+      object: testRunner
+      arguments:
+        client: *client0
+        failPoint:
+          configureFailPoint: failCommand
+          mode: { times: 1 }
+          data:
+            failCommands: ["insert"]
+            closeConnection: true
+
+
+targetedFailPoint
+~~~~~~~~~~~~~~~~~
+
+The ``targetedFailPoint`` operation instructs the test runner to configure a
+fail point on a specific mongos using the client entity associated with a
+pinned session.
+
+The following arguments are supported:
+
+- ``failPoint``: Required document. The ``configureFailPoint`` command to be
+  executed.
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+  The client entity associated with this session SHOULD specify true for
+  `useMultipleMongoses <entity_client_useMultipleMongoses_>`_. This is advised
+  because multiple mongos connections are necessary to test session pinning.
+
+The MongoClient and mongos on which to run the ``configureFailPoint`` command is
+determined by the ``session`` argument (after resolution to a session entity).
+Test runners MUST error if the session is not pinned to a mongos server at the
+time this operation is executed.
+
+When executing this operation, the test runner MUST keep a record of both the
+fail point and session (or pinned mongos server) so that the fail point can be
+disabled on the same mongos server after the test. The test runner MUST also
+ensure that the ``configureFailPoint`` command is excluded from the list of
+observed command monitoring events for this client (if applicable).
+
+An example of this operation follows::
+
+    # Enable the fail point on the mongos to which session0 is pinned
+    - name: targetedFailPoint
+      object: testRunner
+      arguments:
+        session: *session0
+        failPoint:
+          configureFailPoint: failCommand
+          mode: { times: 1 }
+          data:
+            failCommands: ["commitTransaction"]
+            closeConnection: true
+
+
+assertSessionTransactionState
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertSessionTransactionState`` operation instructs the test runner to
+assert that the given session has a particular transaction state.
+
+The following arguments are supported:
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+- ``state``: Required string. Expected transaction state for the session.
+  Possible values are as follows: ``none``, ``starting``, ``in_progress``,
+  ``committed``, and ``aborted``.
+
+An example of this operation follows::
+
+    - name: assertSessionTransactionState
+      object: testRunner
+      arguments:
+        session: *session0
+        state: in_progress
+
+
+assertSessionPinned
+~~~~~~~~~~~~~~~~~~~
+
+The ``assertSessionPinned`` operation instructs the test runner to assert that
+the given session is pinned to a mongos server.
+
+The following arguments are supported:
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+An example of this operation follows::
+
+    - name: assertSessionPinned
+      object: testRunner
+      arguments:
+        session: *session0
+
+
+assertSessionUnpinned
+~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertSessionUnpinned`` operation instructs the test runner to assert that
+the given session is not pinned to a mongos server.
+
+The following arguments are supported:
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+An example of this operation follows::
+
+    - name: assertSessionUnpinned
+      object: testRunner
+      arguments:
+        session: *session0
+
+
+assertDifferentLsidOnLastTwoCommands
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertDifferentLsidOnLastTwoCommands`` operation instructs the test runner
+to assert that the last two CommandStartedEvents observed on the client have
+different ``lsid`` fields. This assertion is primarily used to test that dirty
+server sessions are discarded from the pool.
+
+The following arguments are supported:
+
+- ``client``: Required string. See `commonOptions_client`_.
+
+  The client entity SHOULD include "commandStartedEvent" in
+  `observeEvents <entity_client_observeEvents_>`_.
+
+The test runner MUST fail this assertion if fewer than two CommandStartedEvents
+have been observed on the client or if either command does not include an
+``lsid`` field.
+
+An example of this operation follows::
+
+    - name: assertDifferentLsidOnLastTwoCommands
+      object: testRunner
+      arguments:
+        client: *client0
+
+
+assertSameLsidOnLastTwoCommands
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertSameLsidOnLastTwoCommands`` operation instructs the test runner to
+assert that the last two CommandStartedEvents observed on the client have
+identical ``lsid`` fields. This assertion is primarily used to test that
+non-dirty server sessions are not discarded from the pool.
+
+The following arguments are supported:
+
+- ``client``: Required string. See `commonOptions_client`_.
+
+  The client entity SHOULD include "commandStartedEvent" in
+  `observeEvents <entity_client_observeEvents_>`_.
+
+The test runner MUST fail this assertion if fewer than two CommandStartedEvents
+have been observed on the client or if either command does not include an
+``lsid`` field.
+
+An example of this operation follows::
+
+    - name: assertSameLsidOnLastTwoCommands
+      object: testRunner
+      arguments:
+        client: *client0
+
+
+assertSessionDirty
+~~~~~~~~~~~~~~~~~~
+
+The ``assertSessionDirty`` operation instructs the test runner to assert that
+the given session is marked dirty.
+
+The following arguments are supported:
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+An example of this operation follows::
+
+    - name: assertSessionDirty
+      object: testRunner
+      arguments:
+        session: *session0
+
+
+assertSessionNotDirty
+~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertSessionNotDirty`` operation instructs the test runner to assert that
+the given session is not marked dirty.
+
+The following arguments are supported:
+
+- ``session``: Required string. See `commonOptions_session`_.
+
+An example of this operation follows::
+
+    - name: assertSessionNotDirty
+      object: testRunner
+      arguments:
+        session: *session0
+
+
+assertCollectionExists
+~~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertCollectionExists`` operation instructs the test runner to assert
+that the given collection exists in the database. The test runner MUST use the
+internal MongoClient for this operation.
+
+The following arguments are supported:
+
+- ``collectionName``: Required string. See `commonOptions_collectionName`_.
+
+- ``databaseName``: Required string. See `commonOptions_databaseName`_.
+
+An example of this operation follows::
+
+    - name: assertCollectionExists
+      object: testRunner
+      arguments:
+        collectionName: *collection0Name
+        databaseName:  *database0Name
+
+Use a ``listCollections`` command to check whether the collection exists. Note
+that it is currently not possible to run ``listCollections`` from within a
+transaction.
+
+
+assertCollectionNotExists
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``assertCollectionNotExists`` operation instructs the test runner to assert
+that the given collection does not exist in the database. The test runner MUST
+use the internal MongoClient for this operation.
+
+The following arguments are supported:
+
+- ``collectionName``: Required string. See `commonOptions_collectionName`_.
+
+- ``databaseName``: Required string. See `commonOptions_databaseName`_.
+
+An example of this operation follows::
+
+    - name: assertCollectionNotExists
+      object: testRunner
+      arguments:
+        collectionName: *collection0Name
+        databaseName:  *database0Name
+
+Use a ``listCollections`` command to check whether the collection exists. Note
+that it is currently not possible to run ``listCollections`` from within a
+transaction.
+
+
+assertIndexExists
+~~~~~~~~~~~~~~~~~
+
+The ``assertIndexExists`` operation instructs the test runner to assert that an
+index with the given name exists on the collection. The test runner MUST use the
+internal MongoClient for this operation.
+
+The following arguments are supported:
+
+- ``collectionName``: Required string. See `commonOptions_collectionName`_.
+
+- ``databaseName``: Required string. See `commonOptions_databaseName`_.
+
+- ``indexName``: Required string. Index name.
+
+An example of this operation follows::
+
+    - name: assertIndexExists
+      object: testRunner
+      arguments:
+        collectionName: *collection0Name
+        databaseName:  *database0Name
+        indexName: t_1
+
+Use a ``listIndexes`` command to check whether the index exists. Note that it is
+currently not possible to run ``listIndexes`` from within a transaction.
+
+
+assertIndexNotExists
+~~~~~~~~~~~~~~~~~~~~
+
+The ``assertIndexNotExists`` operation instructs the test runner to assert that
+an index with the given name does not exist on the collection. The test runner
+MUST use the internal MongoClient for this operation.
+
+- ``collectionName``: Required string. See `commonOptions_collectionName`_.
+
+- ``databaseName``: Required string. See `commonOptions_databaseName`_.
+
+- ``indexName``: Required string. Index name.
+
+An example of this operation follows::
+
+    - name: assertIndexNotExists
+      object: testRunner
+      arguments:
+        collectionName: *collection0Name
+        databaseName:  *database0Name
+        indexName: t_1
+
+Use a ``listIndexes`` command to check whether the index exists. Note that it is
+currently not possible to run ``listIndexes`` from within a transaction.
+
+
+Evaluating Matches
+------------------
+
+Expected values in tests (e.g.
+`operation.expectResult <operation_expectResult_>`_) are expressed as either
+relaxed or canonical `Extended JSON <../extended-json.rst>`_.
+
+The algorithm for matching expected and actual values is specified with the
+following pseudo-code::
+
+    function match (expected, actual):
+      if expected is a document:
+        // handle special operators (e.g. $$type)
+        if first and only key of expected starts with "$$":
+          execute any assertion(s) for the special operator
+          return
+
+        assert that actual is a document
+
+        for every key/value in expected:
+          // handle key-based operators (e.g. $$exists, $$unsetOrMatches)
+          if value is a document and its first and only key starts with "$$":
+            execute any assertion(s) for the special operator
+            continue to the next iteration unless actual value must be matched
+
+          assert that actual[key] exists
+          assert that actual[key] matches value
+
+        if expected is not the root document:
+          assert that actual does not contain additional keys
+
+        return
+
+      if expected is an array:
+        assert that actual is an array
+        assert that actual and expected have the same number of elements
+
+        for every index/value in expected:
+          assert that actual[index] matches value
+
+        return
+
+      // expected is neither a document nor array
+      assert that actual and expected are the same type, noting flexible numerics
+      assert that actual and expected are equal
+
+The rules for comparing documents and arrays are discussed in more detail in
+subsequent sections. When comparing types *other* than documents and arrays,
+test runners MAY adopt any of the following approaches to compare expected and
+actual values, as long as they are consistent:
+
+- Convert both values to relaxed or canonical `Extended JSON`_ and compare
+  strings
+- Convert both values to BSON, and compare bytes
+- Convert both values to native representations, and compare accordingly
+
+When comparing types that contain documents as internal properties (e.g.
+CodeWScope), the rules in `Evaluating Matches`_ do not apply and the documents
+MUST match exactly; however, test runners MUST permit variation in document key
+order or otherwise normalize the documents before comparison.
+
+
+Flexible Numeric Comparisons
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When comparing numeric types (excluding Decimal128), test runners MUST consider
+32-bit, 64-bit, and floating point numbers to be equal if their values are
+numerically equivalent. For example, an expected value of ``1`` would match an
+actual value of ``1.0`` (e.g. ``ok`` field in a server response) but would not
+match ``1.5``.
+
+
+Allowing Extra Fields in Root-level Documents
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When matching root-level documents, test runners MUST permit the actual document
+to contain additional fields not present in the expected document. Examples of
+root-level documents include, but are not limited to:
+
+- ``command`` for `CommandStartedEvent <expectedEvent_commandStartedEvent_>`_
+- ``reply`` for `CommandSucceededEvent <expectedEvent_commandSucceededEvent_>`_
+- `expectResult`_ for ``findOneAndUpdate`` `Collection Operations`_
+- `expectResult`_ for `iterateUntilDocumentOrError`_ `ChangeStream Operations`_
+- each array element in `expectResult`_ for `find`_ or `aggregate`_
+  `Collection Operations`_
+
+For example, the following documents match::
+
+    expected: { x: 1 }
+    actual: { x: 1, y: 1 }
+
+The inverse is not true. For example, the following documents do not match::
+
+    expected: { x: 1, y: 1 }
+    actual: { x: 1 }
+
+Test runners MUST NOT permit additional fields in nested documents. For example,
+the following documents do not match::
+
+    expected: { x: { y: 1 } }
+    actual: { x: { y: 1, z: 1 } }
+
+It may be helpful to think of expected documents as a form of query criteria.
+The intention behind this rule is that it is not always feasible or relevant for
+a test to exhaustively specify all fields in an expected document (e.g. cluster
+time in ``command`` for `CommandStartedEvent`_).
+
+When the expected value is an array, test runners MUST differentiate between
+an array of values, which may be documents, (e.g. ``distinct``) and an array of
+root-level documents (e.g. ``find``, ``aggregate``). For example, the following
+array of documents would not match if returned by ``distinct``, but would match
+if returned via ``find`` (after iterating the cursor):
+
+    expected: [ { x: 1 }, { x: 2 } ]
+    actual: [ { x: 1, y: 1 }, { x: 2, y: 2 } ]
+
+
+Document Key Order Variation
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When matching documents, test runners MUST NOT require keys in the expected and
+actual document to appear in the same order. For example, the following
+documents would match:
+
+    expected: { x: 1, y: 1 }
+    actual: { y: 1, x: 1 }
+
+
+Arrays Must Contain the Same Number of Elements
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When comparing arrays, expected and actual values MUST contain the same number
+of elements. For example, the following arrays corresponding to a ``distinct``
+operation result would not match::
+
+    expected: [ 1, 2, 3 ]
+    actual: [ 1, 2, 3, 4 ]
+
+
+Special Operators for Matching Assertions
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When matching expected and actual values, an equality comparison is not always
+sufficient. For instance, a test file cannot anticipate what a session ID will
+be at runtime, but may still want to analyze the contents of an ``lsid`` field
+in a command document. To address this need, special operators can be used.
+
+These operators are objects with a single key identifying the operator. Such
+keys are prefixed with ``$$`` to ease in detecting an operator (test runners
+need only inspect the first key of each object) and differentiate the object
+from MongoDB query operators, which use a single `$` prefix. The key will map to
+some value that influences the operator's behavior (if applicable).
+
+When examining the structure of an expected value during a comparison, test
+runners MUST check if the value is an object whose first and only key starts
+with ``$$`` and, if so, defer to the special logic defined in this section.
+
+
+$$exists
+````````
+
+Syntax::
+
+    { field: { $$exists: <boolean> } }
+
+This operator can be used anywhere the value for a key might be specified in an
+expected document. If true, the test runner MUST assert that the key exists in
+the actual document, irrespective of its value (e.g. a key with a ``null`` value
+would match). If false, the test runner MUST assert that the key does not exist
+in the actual document. This operator is modeled after the
+`$exists <https://docs.mongodb.com/manual/reference/operator/query/exists/>`__
+query operator.
+
+An example of this operator checking for a field's presence follows::
+
+    command:
+      getMore: { $$exists: true }
+      collection: *collectionName,
+      batchSize: 5
+
+An example of this operator checking for a field's absence follows::
+
+    command:
+      update: *collectionName
+      updates: [ { q: {}, u: { $set: { x: 1 } } } ]
+      ordered: true
+      writeConcern: { $$exists: false }
+
+
+$$type
+``````
+
+Syntax::
+
+    { $$type: <string> }
+    { $$type: [ <string>, <string>, ... ] }
+
+This operator can be used anywhere a matched value is expected (including
+`expectResult <operation_expectResult_>`_). The test runner MUST assert that the
+actual value exists and matches one of the expected types, which correspond to
+the documented string types for the
+`$type <https://docs.mongodb.com/manual/reference/operator/query/type/>`__
+query operator.
+
+An example of this operator follows::
+
+    command:
+      getMore: { $$type: [ "int", "long" ] }
+      collection: { $$type: "string" }
+
+When the actual value is an array, test runners MUST NOT examine types of the
+array's elements. Only the type of actual field SHALL be checked. This is
+admittedly inconsistent with the behavior of the
+`$type <https://docs.mongodb.com/manual/reference/operator/query/type/>`__
+query operator, but there is presently no need for this behavior in tests.
+
+
+$$matchesEntity
+```````````````
+
+Syntax, where ``entityName`` is a string::
+
+    { $$matchesEntity: <entityName> }
+
+This operator can be used anywhere a matched value is expected (including
+`expectResult <operation_expectResult_>`_). If the entity name is defined in the
+current test's `Entity Map`_, the test runner MUST fetch that entity and assert
+that the actual value matches the entity using the standard rules in
+`Evaluating Matches`_; otherwise, the test runner MUST raise an error for an
+undefined entity. The YAML file SHOULD use an `alias node`_ for the entity name.
+
+This operator is primarily used to assert identifiers for uploaded GridFS files.
+
+An example of this operator follows::
+
+    operations:
+      -
+        object: *bucket0
+        name: upload
+        arguments:
+          filename: "filename"
+          source: { $$hexBytes: "12AB" }
+        expectResult: { $$type: "objectId" }
+        saveResultAsEntity: &objectid0 "objectid0"
+      - object: *filesCollection
+        name: find
+        arguments:
+          sort: { uploadDate: -1 }
+          limit: 1
+        expectResult:
+          - _id: { $$matchesEntity: *objectid0 }
+
+
+$$matchesHexBytes
+`````````````````
+
+Syntax, where ``hexBytes`` is an even number of hexademical characters
+(case-insensitive) and MAY be empty::
+
+    { $$matchesHexBytes: <hexBytes> }
+
+This operator can be used anywhere a matched value is expected (including
+`expectResult <operation_expectResult_>`_) and the actual value is a string.
+The test runner MUST raise an error if the ``hexBytes`` string is malformed.
+This operator is primarily used to assert the results of `download`_ and
+`downloadByName`_, which return stream contents as a string.
+
+
+$$unsetOrMatches
+````````````````
+
+Syntax::
+
+    { $$unsetOrMatches: <anything> }
+
+This operator can be used anywhere a matched value is expected (including
+`expectResult <operation_expectResult_>`_), excluding an array element because
+`Arrays Must Contain the Same Number of Elements`_. The test runner MUST assert
+that the actual value either does not exist or matches the expected value.
+Matching the expected value MUST use the standard rules in
+`Evaluating Matches`_, which means that it may contain special operators.
+
+This operator is primarily used to assert driver-optional fields from the CRUD
+spec (e.g. ``insertedId`` for InsertOneResult, ``writeResult`` for
+BulkWriteException).
+
+An example of this operator used for a result's field follows::
+
+    expectResult:
+      insertedId: { $$unsetOrMatches: 2 }
+
+An example of this operator used for an entire result follows::
+
+    expectError:
+      expectResult:
+        $$unsetOrMatches:
+          deletedCount: 0
+          insertedCount: 2
+          matchedCount: 0
+          modifiedCount: 0
+          upsertedCount: 0
+          upsertedIds: { }
+
+
+$$sessionLsid
+`````````````
+
+Syntax::
+
+    { $$sessionLsid: <sessionEntityName> }
+
+This operator can be used anywhere a matched value is expected (including
+`expectResult <operation_expectResult_>`_).  If the
+`session entity <entity_session_>`_ is defined in the current test's
+`Entity Map`_, the test runner MUST assert that the actual value equals its
+logical session ID; otherwise, the test runner MUST raise an error for an
+undefined or mistyped entity. The YAML file SHOULD use an `alias node`_ for a
+session entity's ``id`` field (e.g. ``session: *session0``).
+
+An example of this operator follows::
+
+    command:
+      ping: 1
+      lsid: { $$sessionLsid: *session0 }
+
+
+Test Runner Implementation
+--------------------------
+
+The sections below describe instructions for instantiating the test runner,
+loading each test file, and executing each test within a test file. Test runners
+MUST NOT share state created by processing a test file with the processing of
+subsequent test files, and likewise for tests within a test file.
+
+
+Initializing the Test Runner
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The test runner MUST be configurable with a connection string (or equivalent
+configuration), which will be used to initialize the internal MongoClient and
+any `client entities <entity_client_>`_ (in combination with other URI options).
+This specification is not prescriptive about how this information is provided.
+For example, it may be read from an environment variable or configuration file.
+
+Create a new MongoClient, which will be used for internal operations (e.g.
+processing `initialData`_ and `test.outcome <test_outcome_>`_). This is referred
+to elsewhere in the specification as the internal MongoClient.
+
+Determine the server version and topology type using the internal MongoClient.
+This information will be used to evaluate any future `runOnRequirement`_ checks.
+
+The test runner SHOULD terminate any open transactions (see:
+`Terminating Open Transactions`_) using the internal MongoClient before
+executing any tests.
+
+
+Executing a Test File
+~~~~~~~~~~~~~~~~~~~~~
+
+The instructions in this section apply for each test file loaded by the test
+runner.
+
+Test files, which may be YAML or JSON files, MUST be interpreted using an
+`Extended JSON`_ parser. The parser MUST accept relaxed and canonical Extended
+JSON (per `Extended JSON: Parsers <../extended-json.rst#parsers>`__), as test
+files may use either.
+
+Upon loading a file, the test runner MUST read the `schemaVersion`_ field and
+determine if the test file can be processed further. Test runners MAY support
+multiple versions and MUST NOT process incompatible files (as discussed in
+`Test Runner Support`_). If a test file is incompatible, test runners MUST raise
+an error and MAY do so by reporting a test failure. Test runners MAY make an
+effort to infer the number of tests (and their descriptions) from an
+incompatible file and report a failure for each test.
+
+If `runOnRequirements`_ is specified, the test runner MUST skip the test file
+unless one or more `runOnRequirement`_ objects are satisfied.
+
+For each element in `tests`_, follow the process in `Executing a Test`_.
+
+
+Executing a Test
+~~~~~~~~~~~~~~~~
+
+The instructions in this section apply for each `test`_ occuring in a test file
+loaded by the test runner. After processing a test, test runners MUST reset
+any internal state that resulted from doing so. For example, the `Entity Map`_
+created for one test MUST NOT be shared with another.
+
+If at any point while executing this test an unexpected error is encountered or
+an assertion fails, the test runner MUST consider this test to have failed and
+SHOULD continue with the instructions in this section to ensure that the test
+environment is cleaned up (e.g. disable fail points, kill sessions) while also
+forgoing any additional assertions.
+
+If `test.skipReason <test_skipReason_>`_ is specified, the test runner MUST skip
+this test and MAY use the string value to log a message.
+
+If `test.runOnRequirements <test_runOnRequirements_>`_ is specified, the test
+runner MUST skip the test unless one or more `runOnRequirement`_ objects are
+satisfied.
+
+If `initialData`_ is specified, for each `collectionData`_ therein the test
+runner MUST drop the collection and insert the specified documents (if any)
+using a "majority" write concern. If no documents are specified, the test runner
+MUST create the collection with a "majority" write concern. The test runner
+MUST use the internal MongoClient for these operations.
+
+Create a new `Entity Map`_ that will be used for this test. If `createEntities`_
+is specified, the test runner MUST create each `entity`_ accordingly and add it
+to the map. If the topology is a sharded cluster, the test runner MUST handle
+`useMultipleMongoses`_ accordingly if it is specified for any client entities.
+
+If the test might execute a ``distinct`` command within a sharded transaction,
+for each target collection the test runner SHOULD execute a non-transactional
+``distinct`` command on each mongos server using the internal MongoClient. See
+`StaleDbVersion Errors on Sharded Clusters`_ for more information.
+
+If the test might execute a ``configureFailPoint`` command, for each target
+client the test runner MAY specify a reduced value for ``heartbeatFrequencyMS``
+(and ``minHeartbeatFrequencyMS`` if possible) to speed up SDAM recovery time and
+server selection after a failure; however, test runners MUST NOT do so for any
+client that specifies ``heartbeatFrequencyMS`` in its ``uriOptions``. 
+
+For each client entity where `observeEvents <entity_client_observeEvents_>`_
+has been specified, the test runner MUST enable all event listeners necessary to
+collect the specified event types. Test runners MAY leave event listeners
+disabled for tests that do not assert events (i.e. tests that omit both
+`test.expectEvents <test_expectEvents_>`_ and special operations such as
+`assertSameLsidOnLastTwoCommands`_).
+
+For each client with command monitoring enabled, the test runner MUST ignore
+events for the following:
+
+- Any command(s) specified in
+  `ignoreCommandMonitoringEvents <entity_client_ignoreCommandMonitoringEvents_>`_.
+
+- Any ``configureFailPoint`` commands executed for `failPoint`_ and
+  `targetedFailPoint`_ operations.
+
+- Any commands containing sensitive information (per the
+  `Command Monitoring <../command-monitoring/command-monitoring.rst#security>`__
+  spec).
+
+For each element in `test.operations <test_operations_>`_, follow the process
+in `Executing an Operation`_. If an unexpected error is encountered or an
+assertion fails, the test runner MUST consider this test to have failed.
+
+If any event listeners were enabled on any client entities, the test runner MUST
+now disable those event listeners.
+
+If any fail points were configured, the test runner MUST now disable those fail
+points (on the same server) to avoid spurious failures in subsequent tests. For
+any fail points configured using `targetedFailPoint`_, the test runner MUST
+disable the fail point on the same mongos server on which it was originally
+configured. See `Disabling Fail Points`_ for more information.
+
+If `test.expectEvents <test_expectEvents_>`_ is specified, for each object
+therein the test runner MUST assert that the number and sequence of expected
+events match the number and sequence of actual events observed on the specified
+client. If the list of expected events is empty, the test runner MUST assert
+that no events were observed on the client. The process for matching events is
+described in `expectedEvent`_.
+
+If `test.outcome <test_outcome_>`_ is specified, for each `collectionData`_
+therein the test runner MUST assert that the collection contains exactly the
+expected data. The test runner MUST query each collection using the internal
+MongoClient, an ascending sort order on the ``_id`` field (i.e. ``{ _id: 1 }``),
+a "primary" read preference, a "local" read concern. When comparing collection
+data, the rules in `Evaluating Matches`_ do not apply and the documents MUST
+match exactly; however, test runners MUST permit variations in document key
+order or otherwise normalize the documents before comparison. If the list of
+documents is empty, the test runner MUST assert that the collection is empty.
+
+Clear the entity map for this test. For each ClientSession in the entity map,
+the test runner MUST end the session (e.g. call
+`endSession <../sessions/driver-sessions.rst#endsession>`_).
+
+If the test failed, the test runner MUST terminate any open transactions (see:
+`Terminating Open Transactions`_).
+
+Proceed to the subsequent test.
+
+
+Executing an Operation
+~~~~~~~~~~~~~~~~~~~~~~
+
+The instructions in this section apply for each `operation`_ occuring in a
+`test`_ contained within a test file loaded by the test runner.
+
+If at any point while executing an operation an unexpected error is encountered
+or an assertion fails, the test runner MUST consider the parent test to have
+failed and proceed from `Executing a Test`_ accordingly.
+
+If `operation.object <operation_object_>`_ is "testRunner", this is a special
+operation. If `operation.name <operation_name_>`_ is defined in
+`Special Test Operations`_, the test runner MUST execute the operation
+accordingly and, if successful, proceed to the next operation in the test;
+otherwise, the test runner MUST raise an error for an undefined operation. The
+test runner MUST keep a record of any fail points configured by special
+operations so that they may be disabled after the current test.
+
+If `operation.object`_ is not "testRunner", this is an entity operation. If
+`operation.object`_ is defined in the current test's `Entity Map`_, the test
+runner MUST fetch that entity and note its type; otherwise, the test runner
+MUST raise an error for an undefined entity. If `operation.name`_ does not
+correspond to a known operation for the entity type (per
+`Entity Test Operations`_), the test runner MUST raise an error for an
+unsupported operation. Test runners MAY skip tests that include operations that
+are intentionally unimplemented (e.g.
+``listCollectionNames``).
+
+Proceed with preparing the operation's arguments. If ``session`` is specified in
+`operation.arguments <operation_arguments_>`_, the test runner MUST resolve it
+to a session entity and MUST raise an error if the name is undefined or maps to
+an unexpected type. If a key in `operation.arguments`_ does not correspond to a
+known parameter/option for the operation, the test runner MUST raise an error
+for an unsupported argument.
+
+Before executing the operation, the test runner MUST be prepared to catch a
+potential error from the operation (e.g. enter a ``try`` block). Proceed with
+executing the operation and capture its result or error.
+
+Note that some operations require special handling, as discussed in
+`Entity Test Operations`_. For example, model objects may need to be converted
+to documents (before matching or saving in the entity map) and returned
+iterables may need to be fully iterated.
+
+If `operation.expectError <operation_expectError_>`_ is specified, the test
+runner MUST assert that the operation yielded an error; otherwise, the test
+runner MUST assert that the operation did not yield an error. If an error was
+expected, the test runner MUST evaluate any assertions in `expectedError`_
+accordingly.
+
+If `operation.expectResult <operation_expectResult_>`_ is specified, the test
+MUST assert that it matches the actual result of the operation according to the
+rules outlined in `Evaluating Matches`_.
+
+If `operation.saveResultAsEntity <operation_saveResultAsEntity_>`_ is specified,
+the test runner MUST store the result in the current test's entity map using the
+specified name. If the operation did not return a result or the result does not
+comply with `Supported Entity Types`_ then the test runner MUST raise an error.
+
+After asserting the operation's error and/or result and optionally saving the
+result, proceed to the subsequent operation.
+
+
+Special Procedures
+~~~~~~~~~~~~~~~~~~
+
+This section describes some procedures that may be referenced from earlier
+sections.
+
+
+Terminating Open Transactions
+`````````````````````````````
+
+Open transactions can cause tests to block indiscriminately. Test runners SHOULD
+terminate all open transactions at the start of a test suite and after each
+failed test by killing all sessions in the cluster. Using the internal
+MongoClient, execute the ``killAllSessions`` command on either the primary or,
+if connected to a sharded cluster, all mongos servers.
+
+For example::
+
+    db.adminCommand({
+      killAllSessions: []
+    });
+
+The test runner MAY ignore any command failure with error Interrupted(11601) to
+work around `SERVER-38335`_.
+
+.. _SERVER-38335: https://jira.mongodb.org/browse/SERVER-38335
+
+
+StaleDbVersion Errors on Sharded Clusters
+`````````````````````````````````````````
+
+When a shard receives its first command that contains a ``databaseVersion``, the
+shard returns a StaleDbVersion error and mongos retries the operation. In a
+sharded transaction, mongos does not retry these operations and instead returns
+the error to the client. For example::
+
+    Command distinct failed: Transaction aa09e296-472a-494f-8334-48d57ab530b6:1 was aborted on statement 0 due to: an error from cluster data placement change :: caused by :: got stale databaseVersion response from shard sh01 at host localhost:27217 :: caused by :: don't know dbVersion.
+
+To workaround this limitation, a test runners MUST execute a non-transactional
+``distinct`` command on each mongos server before running any test that might
+execute ``distinct`` within a transaction. To ease the implementation, test
+runners MAY execute ``distinct`` before *every* test.
+
+Test runners can remove this workaround once `SERVER-39704`_ is resolved, after
+which point mongos should retry the operation transparently. The ``distinct``
+command is the only command allowed in a sharded transaction that uses the
+``databaseVersion`` concept so it is the only command affected.
+
+.. _SERVER-39704: https://jira.mongodb.org/browse/SERVER-39704
+
+
+Server Fail Points
+------------------
+
+Many tests utilize the ``configureFailPoint`` command to trigger server-side
+errors such as dropped connections or command errors. Tests can configure fail
+points using the special `failPoint`_ or `targetedFailPoint`_ opertions.
+
+This internal command is not documented in the MongoDB manual (pending
+`DOCS-10784`_); however, there is scattered documentation available on the
+server wiki (`The "failCommand" Fail Point <failpoint-wiki_>`_) and employee
+blogs (e.g. `Intro to Fail Points <failpoint-blog1_>`_,
+`Testing Network Errors with MongoDB <failpoint-blog2_>`_). Documentation can
+also be gleaned from JIRA tickets (e.g. `SERVER-35004`_, `SERVER-35083`_). This
+specification does not aim to provide comprehensive documentation for all fail
+points available for driver testing, but some fail points are documented in
+`Fail Points Commonly Used in Tests`_.
+
+.. _failpoint-wiki: https://github.com/mongodb/mongo/wiki/The-%22failCommand%22-fail-point
+.. _failpoint-blog1: https://kchodorow.com/2013/01/15/intro-to-fail-points/
+.. _failpoint-blog2: https://emptysqua.re/blog/mongodb-testing-network-errors/
+.. _DOCS-10784: https://jira.mongodb.org/browse/DOCS-10784
+.. _SERVER-35004: https://jira.mongodb.org/browse/SERVER-35004
+.. _SERVER-35083: https://jira.mongodb.org/browse/SERVER-35083
+
+
+Configuring Fail Points
+~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``configureFailPoint`` command is executed on the ``admin`` database and has
+the following structure::
+
+    db.adminCommand({
+        configureFailPoint: <string>,
+        mode: <string|object>,
+        data: <object>
+    });
+
+The value of ``configureFailPoint`` is a string denoting the fail point to be
+configured (e.g. "failCommand").
+
+The ``mode`` option is a generic fail point option and may be assigned a string
+or object value. The string values "alwaysOn" and "off" may be used to enable or
+disable the fail point, respectively. An object may be used to specify either
+``times`` or ``skip``, which are mutually exclusive:
+
+- ``{ times: <integer> }`` may be used to limit the number of times the fail
+  point may trigger before transitioning to "off".
+- ``{ skip: <integer> }`` may be used to defer the first trigger of a fail
+  point, after which it will transition to "alwaysOn".
+
+The ``data`` option is an object that may be used to specify any options that
+control the particular fail point's behavior.
+
+In order to use ``configureFailPoint``, the undocumented ``enableTestCommands``
+`server parameter <https://docs.mongodb.com/manual/reference/parameters/>`_ must
+be enabled by either the configuration file or command line option (e.g.
+``--setParameter enableTestCommands=1``). It cannot be enabled at runtime via
+the `setParameter <https://docs.mongodb.com/manual/reference/command/setParameter/>`_
+command). This parameter should already be enabled for most configuration files
+in `mongo-orchestration <https://github.com/10gen/mongo-orchestration>`_.
+
+
+Disabling Fail Points
+~~~~~~~~~~~~~~~~~~~~~
+
+A fail point may be disabled like so::
+
+    db.adminCommand({
+        configureFailPoint: <string>,
+        mode: "off"
+    });
+
+
+Fail Points Commonly Used in Tests
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+
+failCommand
+```````````
+
+The ``failCommand`` fail point allows the client to force the server to return
+an error for commands listed in the ``data.failCommands`` field. Additionally,
+this fail point is documented in server wiki:
+`The failCommand Fail Point <https://github.com/mongodb/mongo/wiki/The-%22failCommand%22-fail-point>`__.
+
+The ``failCommand`` fail point may be configured like so::
+
+    db.adminCommand({
+        configureFailPoint: "failCommand",
+        mode: <string|object>,
+        data: {
+          failCommands: [<string>, ...],
+          closeConnection: <boolean>,
+          errorCode: <integer>,
+          writeConcernError: <object>,
+          appName: <string>,
+          blockConnection: <boolean>,
+          blockTimeMS: <integer>,
+        }
+    });
+
+``failCommand`` supports the following ``data`` options, which may be combined
+if desired:
+
+* ``failCommands``: Required array of strings. Lists the command names to fail.
+* ``closeConnection``: Optional boolean, which defaults to ``false``. If
+  ``true``, the command will not be executed, the connection will be closed, and
+  the client will see a network error.
+* ``errorCode``: Optional integer, which is unset by default. If set, the
+  command will not be executed and the specified command error code will be
+  returned as a command error.
+* ``appName``: Optional string, which is unset by default. If set, the fail
+  point will only apply to connections for MongoClients created with this
+  ``appname``. New in server 4.4.0-rc2
+  (`SERVER-47195 <https://jira.mongodb.org/browse/SERVER-47195>`_).
+* ``blockConnection``: Optional boolean, which defaults to ``false``. If
+  ``true``, the server should block the affected commands for ``blockTimeMS``.
+  New in server 4.3.4
+  (`SERVER-41070 <https://jira.mongodb.org/browse/SERVER-41070>`_).
+* ``blockTimeMS``: Optional integer, which is required when ``blockConnection``
+  is ``true``. The number of milliseconds for which the affected commands should
+  be blocked. New in server 4.3.4
+  (`SERVER-41070 <https://jira.mongodb.org/browse/SERVER-41070>`_).
+
+
+Determining if a Sharded Cluster Uses Replica Sets
+--------------------------------------------------
+
+When connected to a mongos server, the test runner can query the
+`config.shards <https://docs.mongodb.com/manual/reference/config-database/#config.shards>`__
+collection. Each shard in the cluster is represented by a document in this
+collection. If the shard is backed by a single server, the ``host`` field will
+contain a single host. If the shard is backed by a replica set, the ``host``
+field contain the name of the replica followed by a forward slash and a
+comma-delimited list of hosts.
+
+
+Design Rationale
+================
+
+This specification was primarily derived from the test formats used by the
+`Transactions <../transactions/transactions.rst>`__ and
+`CRUD <../crud/crud.rst>`__ specs, which have served models or other specs.
+
+This specification commonly uses "SHOULD" when providing guidance on writing
+test files. While this may appear contradictory to the driver mantra preferring
+"MUST", it is intentional. Some of this guidance addresses style (e.g. adding
+comments, using YAML anchors) and cannot be enforced with a JSON schema. Other
+guidance needs to be purposefully ignored in order to test the test runner
+implementation (e.g. defining entities out of order to trigger runtime errors).
+The specification does prefer "MUST" in other contexts, such as discussing parts
+of the test file format that *are* enforceable by the JSON schema or the test
+runner implementation.
+
+
+Breaking Changes
+================
+
+This section is reserved for future use. Any breaking changes to the test format
+SHOULD be described here in detail for historical reference, in addition to any
+shorter description that may be added to the `Change Log`_.
+
+
+Future Work
+===========
+
+
+Mixing event types in observeEvents and expectEvents
+----------------------------------------------------
+
+The test format advises against mixing events from different specs (e.g. command
+monitoring *and* SDAM) in `observeEvents`_ and `test.expectEvents`_. While
+registering event listeners is trivial, determining how to collate events of
+multiple types can be a challenge, particularly when some events may not be
+predictable (e.g. ServerHeartbeatStartedEvent, CommandStartedEvent for
+``getMore`` issued during change stream iteration). If the need arises to expect
+multiple types of events in the same test, a future version of this spec can
+define an approach for doing so.
+
+
+Support events types beyond command monitoring
+----------------------------------------------
+
+The spec currently only supports command monitoring events in `observeEvents`_
+and `test.expectEvents`_, as those are the only kind of events used in tests for
+specifications that will initially adopt the unified test format. New event
+types (e.g. SDAM) can be added in future versions of the spec as needed, which
+will also require `Mixing event types in observeEvents and expectEvents`_ to be
+addressed.
+
+
+Allow extra observed events to be ignored
+-----------------------------------------
+
+While command monitoring events for specific commands can be ignored (e.g.
+killCursors for change streams), the sequence of observed events must otherwise
+match the sequence of expected events (including length). The present design
+would not support expecting an event for a command while also ignoring extra
+events for the same command (e.g. change stream iteration on a sharded cluster
+where multiple getMore commands may be issued). No spec tests currently require
+this functionality, but that may change in the future.
+
+
+Assert expected log messages
+----------------------------
+
+When drivers support standardized logging, the test format may need to support
+assertions for messages expected to be logged while executing operations. Since
+log messages are strings, this may require an operator to match regex patterns
+within strings. Additionally, the test runner may need to support ignoring extra
+log output, similar to `Allow extra observed events to be ignored`_.
+
+
+Target failPoint by read preference
+-----------------------------------
+
+The `failPoint`_ operation currently uses a "primary" read preference. To date,
+no spec has needed behavior to configure a fail point on a non-primary node. If
+the need does arise, `failPoint`_ can be enhanced to support a
+``readPreference`` argument.
+
+
+IO operations for GridFS streams
+--------------------------------
+
+Original GridFS spec tests refer to "upload", "download", and "download_by_name"
+methods, which allow the tests to abstract stream IO and either upload a byte
+sequence or assert a downloaded byte sequence. These operations correspond to
+the `download`_, `downloadByName`_, `upload`_, and `uploadWithId`_
+`Bucket Operations`_.
+
+In order to support methods such as ``downloadToStream``, ``openUploadStream``,
+and ``openUploadStreamWithId``, test runners would need to represent streams as
+entities and support IO operations to directly read from and write to a stream
+entity. This may not be worth the added complexity if the existing operations
+provide adequate test coverage for GridFS implementations.
+
+
+Support Client-side Encryption integration tests
+------------------------------------------------
+
+Supporting client-side encryption spec tests will require the following changes
+to the test format:
+
+- ``json_schema`` will need to be specified when creating a collection, via
+  either the collection entity definition or `initialData`_.
+- ``key_vault_data`` can be expressed via `initialData`_
+- ``autoEncryptOpts`` will need to be specified when defining a client entity.
+  Preparation of this field may require reading AWS credentials from environment
+  variables.
+
+The process for executing tests should not require significant changes, but test
+files will need to express a dependency on mongocryptd.
+
+
+Support SDAM integration tests
+------------------------------
+
+SDAM integration tests should not require test format changes, but will
+introduce several new special test operations for the "testRunner" object. While
+the tests themselves only define expectations for command monitoring events,
+some special operations may require observing additional event types. There are
+also special operations for defining threads and executing operations within
+threads, which may warrant introducing a new "thread" entity type.
+
+
+Incorporate referenced entity operations into the schema version
+----------------------------------------------------------------
+
+The `Schema Version`_ is not impacted by changes to operations defined in other
+specs and referenced in `Entity Test Operations` (e.g. ``find`` for CRUD). The
+`operation.name <operation_name_>`_ and
+`operation.arguments <operation_arguments_>`_ fields are loosely defined in the
+JSON schema as string and object types, respectively.
+
+Ideally, all operations (and their arguments) would be enforced by the JSON
+schema *and* any changes to operations would affect the schema version
+accordingly. For example, a new ``find`` option would warrant a minor version
+bump both for the CRUD spec and this spec and its schema.
+
+As discussed in `Executing an Operation`_, test runners MUST raise errors for
+unsupported operations and arguments. This is a concession until such time that
+better processes can be established for versioning other specs *and* collating
+spec changes developed in parallel or during the same release cycle.
+
+
+Change Log
+==========