sse-pass-http-req

Author: barnuri

.pre-commit-config.yaml

@@ -7,15 +7,29 @@ repos:
       - id: prettier
         types_or: [yaml, json5]
 
-  - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.8.1
+  - repo: local
     hooks:
       - id: ruff-format
+        name: Ruff Format
+        entry: uv run ruff
+        args: [format]
+        language: system
+        types: [python]
+        pass_filenames: false
       - id: ruff
-        args: [--fix, --exit-non-zero-on-fix]
-
-  - repo: local
-    hooks:
+        name: Ruff
+        entry: uv run ruff
+        args: ["check", "--fix", "--exit-non-zero-on-fix"]
+        types: [python]
+        language: system
+        pass_filenames: false
+      - id: pyright
+        name: pyright
+        entry: uv run pyright
+        args: [src]
+        language: system
+        types: [python]
+        pass_filenames: false
       - id: uv-lock-check
         name: Check uv.lock is up to date
         entry: uv lock --check

README.md

@@ -73,15 +73,24 @@ The Model Context Protocol allows applications to provide context for LLMs in a
 
 ### Adding MCP to your python project
 
-We recommend using [uv](https://docs.astral.sh/uv/) to manage your Python projects. In a uv managed python project, add mcp to dependencies by:
+We recommend using [uv](https://docs.astral.sh/uv/) to manage your Python projects. 
 
-```bash
-uv add "mcp[cli]"
-```
+If you haven't created a uv-managed project yet, create one:
+
+   ```bash
+   uv init mcp-server-demo
+   cd mcp-server-demo
+   ```
+
+   Then add MCP to your project dependencies:
+
+   ```bash
+   uv add "mcp[cli]"
+   ```
 
 Alternatively, for projects using pip for dependencies:
 ```bash
-pip install mcp
+pip install "mcp[cli]"
 ```
 
 ### Running the standalone MCP development tools
@@ -185,7 +194,7 @@ mcp = FastMCP("My App", lifespan=app_lifespan)
 @mcp.tool()
 def query_db(ctx: Context) -> str:
     """Tool that uses initialized resources"""
-    db = ctx.request_context.lifespan_context["db"]
+    db = ctx.request_context.lifespan_context.db
     return db.query()
 ```
 

examples/clients/simple-chatbot/mcp_simple_chatbot/main.py

@@ -122,8 +122,10 @@ async def list_tools(self) -> list[Any]:
 
         for item in tools_response:
             if isinstance(item, tuple) and item[0] == "tools":
-                for tool in item[1]:
-                    tools.append(Tool(tool.name, tool.description, tool.inputSchema))
+                tools.extend(
+                    Tool(tool.name, tool.description, tool.inputSchema)
+                    for tool in item[1]
+                )
 
         return tools
 
@@ -282,10 +284,9 @@ def __init__(self, servers: list[Server], llm_client: LLMClient) -> None:
 
     async def cleanup_servers(self) -> None:
         """Clean up all servers properly."""
-        cleanup_tasks = []
-        for server in self.servers:
-            cleanup_tasks.append(asyncio.create_task(server.cleanup()))
-
+        cleanup_tasks = [
+            asyncio.create_task(server.cleanup()) for server in self.servers
+        ]
         if cleanup_tasks:
             try:
                 await asyncio.gather(*cleanup_tasks, return_exceptions=True)

examples/servers/simple-resource/mcp_simple_resource/__main__.py

@@ -1,5 +1,5 @@
 import sys
 
-from server import main
+from .server import main
 
 sys.exit(main())

examples/servers/simple-tool/mcp_simple_tool/__main__.py

@@ -1,5 +1,5 @@
 import sys
 
-from server import main
+from .server import main
 
 sys.exit(main())

pyproject.toml

@@ -29,7 +29,7 @@ dependencies = [
     "starlette>=0.27",
     "sse-starlette>=1.6.1",
     "pydantic-settings>=2.5.2",
-    "uvicorn>=0.23.1",
+    "uvicorn>=0.23.1; sys_platform != 'emscripten'",
 ]
 
 [project.optional-dependencies]
@@ -89,8 +89,8 @@ venv = ".venv"
 strict = ["src/mcp/**/*.py"]
 
 [tool.ruff.lint]
-select = ["E", "F", "I", "UP"]
-ignore = []
+select = ["C4", "E", "F", "I", "PERF", "UP"]
+ignore = ["PERF203"]
 
 [tool.ruff]
 line-length = 88

src/mcp/client/__main__.py

@@ -38,9 +38,13 @@ async def message_handler(
 async def run_session(
     read_stream: MemoryObjectReceiveStream[JSONRPCMessage | Exception],
     write_stream: MemoryObjectSendStream[JSONRPCMessage],
+    client_info: types.Implementation | None = None,
 ):
     async with ClientSession(
-        read_stream, write_stream, message_handler=message_handler
+        read_stream,
+        write_stream,
+        message_handler=message_handler,
+        client_info=client_info,
     ) as session:
         logger.info("Initializing session")
         await session.initialize()

src/mcp/client/session.py

@@ -10,6 +10,8 @@
 from mcp.shared.session import BaseSession, RequestResponder
 from mcp.shared.version import SUPPORTED_PROTOCOL_VERSIONS
 
+DEFAULT_CLIENT_INFO = types.Implementation(name="mcp", version="0.1.0")
+
 
 class SamplingFnT(Protocol):
     async def __call__(
@@ -97,6 +99,7 @@ def __init__(
         list_roots_callback: ListRootsFnT | None = None,
         logging_callback: LoggingFnT | None = None,
         message_handler: MessageHandlerFnT | None = None,
+        client_info: types.Implementation | None = None,
     ) -> None:
         super().__init__(
             read_stream,
@@ -105,6 +108,7 @@ def __init__(
             types.ServerNotification,
             read_timeout_seconds=read_timeout_seconds,
         )
+        self._client_info = client_info or DEFAULT_CLIENT_INFO
         self._sampling_callback = sampling_callback or _default_sampling_callback
         self._list_roots_callback = list_roots_callback or _default_list_roots_callback
         self._logging_callback = logging_callback or _default_logging_callback
@@ -130,7 +134,7 @@ async def initialize(self) -> types.InitializeResult:
                             experimental=None,
                             roots=roots,
                         ),
-                        clientInfo=types.Implementation(name="mcp", version="0.1.0"),
+                        clientInfo=self._client_info,
                     ),
                 )
             ),

src/mcp/server/fastmcp/server.py

@@ -15,7 +15,6 @@
 
 import anyio
 import pydantic_core
-import uvicorn
 from pydantic import BaseModel, Field
 from pydantic.networks import AnyUrl
 from pydantic_settings import BaseSettings, SettingsConfigDict
@@ -466,6 +465,7 @@ async def run_stdio_async(self) -> None:
 
     async def run_sse_async(self) -> None:
         """Run the server using SSE transport."""
+        import uvicorn
         starlette_app = self.sse_app()
 
         config = uvicorn.Config(
@@ -491,6 +491,7 @@ async def handle_sse(request: Request) -> None:
                     streams[0],
                     streams[1],
                     self._mcp_server.create_initialization_options(),
+                    extra_metadata={"http_request": request},
                 )
 
         return Starlette(
@@ -501,6 +502,15 @@ async def handle_sse(request: Request) -> None:
             ],
         )
 
+    def get_http_request(self) -> Request | None:
+        ctx = self.get_context()
+        if (ctx.request_context and
+            ctx.request_context.meta and
+            hasattr(ctx.request_context.meta, "extra_metadata")):
+            req: Request = ctx.request_context.meta.extra_metadata.get("http_request")  # type: ignore
+            return req
+        return None
+
     async def list_prompts(self) -> list[MCPPrompt]:
         """List all available prompts."""
         prompts = self._prompt_manager.list_prompts()

src/mcp/server/fastmcp/tools/base.py

@@ -2,7 +2,7 @@
 
 import inspect
 from collections.abc import Callable
-from typing import TYPE_CHECKING, Any
+from typing import TYPE_CHECKING, Any, get_origin
 
 from pydantic import BaseModel, Field
 
@@ -53,7 +53,9 @@ def from_function(
         if context_kwarg is None:
             sig = inspect.signature(fn)
             for param_name, param in sig.parameters.items():
-                if param.annotation is Context:
+                if get_origin(param.annotation) is not None:
+                    continue
+                if issubclass(param.annotation, Context):
                     context_kwarg = param_name
                     break