Clarify Link Obj parameters as best we can (3.1.1)

This acknowledges the ambiguity in the key and value syntax of the
Link Object's `parameter` field, and provides a bit of guidance
on how to implement it.  Sadly it is not possible to fully solve
in a point release.

Author: handrews

versions/3.1.1.md

@@ -2147,7 +2147,7 @@ Field Name  |  Type  | Description
 ---|:---:|---
 <a name="linkOperationRef"></a>operationRef | `string` | A relative or absolute URI reference to an OAS operation. This field is mutually exclusive of the `operationId` field, and MUST point to an [Operation Object](#operationObject). Relative `operationRef` values MAY be used to locate an existing [Operation Object](#operationObject) in the OpenAPI definition. See the rules for resolving [Relative References](#relativeReferencesURI).
 <a name="linkOperationId"></a>operationId  | `string` | The name of an _existing_, resolvable OAS operation, as defined with a unique `operationId`.  This field is mutually exclusive of the `operationRef` field.  
-<a name="linkParameters"></a>parameters   | Map[`string`, Any \| [{expression}](#runtimeExpression)] | A map representing parameters to pass to an operation as specified with `operationId` or identified via `operationRef`. The key is the parameter name to be used, whereas the value can be a constant or an expression to be evaluated and passed to the linked operation.  The parameter name can be qualified using the [parameter location](#parameterIn) `[{in}.]{name}` for operations that use the same parameter name in different locations (e.g. path\.id).
+<a name="linkParameters"></a>parameters   | Map[`string`, Any \| [{expression}](#runtimeExpression)] | A map representing parameters to pass to an operation as specified with `operationId` or identified via `operationRef`. The key is the parameter name to be used (optionally qualified with the parameter location, e.g. `path.id` for an `id` parameter in the path), whereas the value can be a constant or an expression to be evaluated and passed to the linked operation.
 <a name="linkRequestBody"></a>requestBody | Any \| [{expression}](#runtimeExpression) | A literal value or [{expression}](#runtimeExpression) to use as a request body when calling the target operation.
 <a name="linkDescription"></a>description  | `string` | A description of the link. [CommonMark syntax](https://spec.commonmark.org/) MAY be used for rich text representation.
 <a name="linkServer"></a>server       | [Server Object](#serverObject) | A server object to be used by the target operation.
@@ -2159,6 +2159,9 @@ In the case of an `operationId`, it MUST be unique and resolved in the scope of
 Because of the potential for name clashes, the `operationRef` syntax is preferred 
 for OpenAPI documents with external references.
 
+Note that it is not possible to provide a constant value to `parameters` that matches the syntax of a runtime expression.
+It is possible to have ambiguous parameter names, e.g. `name: id, in: path` and `name: path.id, in: query`; this is NOT RECOMMENDED and the behavior is implementation-defined, however implementations SHOULD prefer the qualified interpretation (`path.id` as a path parameter), as the names can always be qualified to disambiguate them (e.g. using `query.path.id` for the query paramter).
+
 ##### Examples
 
 Computing a link from a request operation where the `$request.path.id` is used to pass a request parameter to the linked operation.