feat: Add custom httpx_client for sse_client call [#1891](https://github.com/whvneo/pydantic-ai/issues/1891)

.devcontainer/Dockerfile

@@ -0,0 +1,47 @@
+FROM python:3.12-bookworm
+
+ARG GIT_USERNAME
+ARG GIT_EMAIL
+ARG USERNAME=coder
+ARG USER_UID=1000
+ARG USER_GID=1000
+ARG WORKSPACE=/home/$USERNAME/workspace
+ARG DEBIAN_FRONTEND=noninteractive
+
+
+ENV SHELL=/bin/bash
+ENV LANG=en_US.UTF-8
+ENV LANGUAGE=en_US.UTF-8
+ENV LC_ALL=en_US.UTF-8
+
+RUN apt -y update \
+    && apt -y upgrade
+
+RUN apt -y install inetutils-ping vim-nox htop git curl wget net-tools 	bind9-dnsutils locales
+RUN sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen && \
+    locale-gen
+ENV LANG=en_US.UTF-8  
+ENV LANGUAGE=en_US:en  
+ENV LC_ALL=en_US.UTF-8     
+
+RUN apt -y autoremove \
+    && apt -y clean \
+    && rm -Rf /var/lib/apt/lists/*
+
+RUN curl -sSL https://install.python-poetry.org | python3 - 
+
+RUN groupadd --gid $USER_GID $USERNAME \
+    && useradd --uid $USER_UID --gid $USER_GID -m $USERNAME \
+    && echo "$USERNAME:$USERNAME" | chpasswd \
+    && adduser $USERNAME sudo
+
+RUN mkdir -p $WORKSPACE \
+    && chown -R $USERNAME:$USERNAME $WORKSPACE \
+    && chmod -R u=rwX,go=rX $WORKSPACE
+
+RUN pip install --no-cache-dir uv
+
+USER $USERNAME
+
+RUN git config --global user.email "$GIT_EMAIL"
+RUN git config --global user.name "$GIT_USERNAME"

.devcontainer/devcontainer.json

@@ -0,0 +1,33 @@
+{
+  "name": "pydantic-ai",
+  "dockerComposeFile": ["docker-compose.yml"],
+  "service": "pydantic-ai",
+  "remoteUser": "coder",
+  "shutdownAction": "stopCompose",
+  "workspaceFolder": "/home/coder/workspace",
+  "customizations": {
+    "vscode": {
+      "settings": {},
+      "extensions": [
+        "anweber.vscode-httpyac",
+        "donjayamanne.python-environment-manager",
+        "esbenp.prettier-vscode",
+        "github.copilot",
+        "github.copilot-chat",
+        "mhutchie.git-graph",
+        "ms-azuretools.vscode-docker",
+        "ms-python.debugpy",
+        "ms-python.python",
+        "ms-python.vscode-pylance",
+        "ms-toolsai.jupyter",
+        "ms-toolsai.jupyter-keymap",
+        "ms-toolsai.jupyter-renderers",
+        "ms-toolsai.vscode-jupyter-cell-tags",
+        "ms-toolsai.vscode-jupyter-slideshow",
+        "visualstudioexptteam.intellicode-api-usage-examples",
+        "visualstudioexptteam.vscodeintellicode"
+      ]
+    }
+  },
+  "runArgs": "--network=maia"
+}

.devcontainer/docker-compose.yml

@@ -0,0 +1,21 @@
+name: pydantic-ai_devcontainer
+
+services:
+  pydantic-ai: 
+    build: 
+      context: .
+      dockerfile: Dockerfile
+      args:
+        - GIT_EMAIL=${GIT_EMAIL}
+        - GIT_USERNAME=${GIT_USERNAME}
+    volumes:
+      - ..:/home/coder/workspace
+      - ~/.ssh:/home/coder/.ssh:ro
+    working_dir: /home/coder/workspace
+    hostname: pydantic-ai
+    command: /bin/sh -c "while sleep 1000; do :; done"
+
+networks:
+  default:
+    external: true
+    name: maia

.gitignore

@@ -19,3 +19,4 @@ examples/pydantic_ai_examples/.chat_app_messages.sqlite
 node_modules/
 **.idea/
 .coverage*
+uv.lock

.pre-commit-config.yaml

@@ -47,13 +47,6 @@ repos:
         language: system
         types_or: [python, markdown]
         pass_filenames: false
-      - id: typecheck
-        name: Typecheck
-        entry: make
-        args: [typecheck]
-        language: system
-        types: [python]
-        pass_filenames: false
 
   - repo: https://github.com/codespell-project/codespell
     # Configuration for codespell is in pyproject.toml

pydantic_ai_slim/pydantic_ai/mcp.py

@@ -25,7 +25,7 @@
 
 from pydantic_ai.exceptions import ModelRetry
 from pydantic_ai.messages import BinaryContent
-from pydantic_ai.tools import ToolDefinition
+from pydantic_ai.tools import McpHttpClientFactory, ToolDefinition, create_mcp_http_client
 
 try:
     from mcp.client.session import ClientSession
@@ -358,6 +358,14 @@ async def main():
     For example, if `tool_prefix='foo'`, then a tool named `bar` will be registered as `foo_bar`
     """
 
+    httpx_client_factory: McpHttpClientFactory = create_mcp_http_client
+    """Factory function to create the underlying HTTPX client.
+
+    This allows customization of the HTTP client used for the SSE connection.
+
+    See <https://github.com/modelcontextprotocol/python-sdk/pull/752>
+    """
+
     @asynccontextmanager
     async def client_streams(
         self,
@@ -372,6 +380,7 @@ async def client_streams(
             headers=self.headers,
             timeout=self.timeout,
             sse_read_timeout=self.sse_read_timeout,
+            httpx_client_factory=self.httpx_client_factory,
         ) as (read_stream, write_stream):
             yield read_stream, write_stream
 

pydantic_ai_slim/pydantic_ai/tools.py

@@ -4,8 +4,9 @@
 import json
 from collections.abc import Awaitable, Sequence
 from dataclasses import dataclass, field
-from typing import TYPE_CHECKING, Any, Callable, Generic, Literal, Union
+from typing import TYPE_CHECKING, Any, Callable, Generic, Literal, Protocol, Union
 
+import httpx
 from opentelemetry.trace import Tracer
 from pydantic import ValidationError
 from pydantic.json_schema import GenerateJsonSchema, JsonSchemaValue
@@ -33,6 +34,8 @@
     'Tool',
     'ObjectJsonSchema',
     'ToolDefinition',
+    'McpHttpClientFactory',
+    'create_mcp_http_client',
 )
 
 AgentDepsT = TypeVar('AgentDepsT', default=None, contravariant=True)
@@ -446,3 +449,85 @@ class ToolDefinition:
     """
 
     __repr__ = _utils.dataclasses_no_defaults_repr
+
+
+class McpHttpClientFactory(Protocol):
+    """HTTP client factory for MCP.
+
+    This protocol defines a callable that creates an `httpx.AsyncClient` with MCP defaults.
+    It allows for customization of headers, timeout, and authentication.
+    """
+
+    def __call__(
+        self,
+        headers: dict[str, str] | None = None,
+        timeout: httpx.Timeout | None = None,
+        auth: httpx.Auth | None = None,
+    ) -> httpx.AsyncClient: ...
+
+
+def create_mcp_http_client(
+    headers: dict[str, str] | None = None,
+    timeout: httpx.Timeout | None = None,
+    auth: httpx.Auth | None = None,
+) -> httpx.AsyncClient:
+    """Create a standardized httpx AsyncClient with MCP defaults.
+
+    This function provides common defaults used throughout the MCP codebase:
+    - follow_redirects=True (always enabled)
+    - Default timeout of 30 seconds if not specified
+
+    Args:
+        headers: Optional headers to include with all requests.
+        timeout: Request timeout as httpx.Timeout object.
+            Defaults to 30 seconds if not specified.
+        auth: Optional authentication handler.
+
+    Returns:
+        Configured httpx.AsyncClient instance with MCP defaults.
+
+    Note:
+        The returned AsyncClient must be used as a context manager to ensure
+        proper cleanup of connections.
+
+    Examples:
+        # Basic usage with MCP defaults
+        async with create_mcp_http_client() as client:
+            response = await client.get("https://api.example.com")
+
+        # With custom headers
+        headers = {"Authorization": "Bearer token"}
+        async with create_mcp_http_client(headers) as client:
+            response = await client.get("/endpoint")
+
+        # With both custom headers and timeout
+        timeout = httpx.Timeout(60.0, read=300.0)
+        async with create_mcp_http_client(headers, timeout) as client:
+            response = await client.get("/long-request")
+
+        # With authentication
+        from httpx import BasicAuth
+        auth = BasicAuth(username="user", password="pass")
+        async with create_mcp_http_client(headers, timeout, auth) as client:
+            response = await client.get("/protected-endpoint")
+    """
+    # Set MCP defaults
+    kwargs: dict[str, Any] = {
+        'follow_redirects': True,
+    }
+
+    # Handle timeout
+    if timeout is None:
+        kwargs['timeout'] = httpx.Timeout(30.0)
+    else:
+        kwargs['timeout'] = timeout
+
+    # Handle headers
+    if headers is not None:
+        kwargs['headers'] = headers
+
+    # Handle authentication
+    if auth is not None:
+        kwargs['auth'] = auth
+
+    return httpx.AsyncClient(**kwargs)

pydantic_ai_slim/pyproject.toml

@@ -43,13 +43,14 @@ classifiers = [
     "Topic :: Software Development :: Libraries :: Python Modules",
     "Topic :: Internet",
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 
 [tool.hatch.metadata.hooks.uv-dynamic-versioning]
 dependencies = [
     "eval-type-backport>=0.2.0",
     "griffe>=1.3.2",
     "httpx>=0.27",
+    "mcp>=1.9.2",
     "pydantic>=2.10",
     "pydantic-graph=={{ version }}",
     "exceptiongroup; python_version < '3.11'",