feat: JSONRPCDispatcher

.github/workflows/main.yml

@@ -5,7 +5,6 @@ on:
     branches: ["main", "v1.x"]
     tags: ["v*.*.*"]
   pull_request:
-    branches: ["main", "v1.x"]
 
 permissions:
   contents: read

src/mcp/shared/direct_dispatcher.py

@@ -20,6 +20,7 @@
 from typing import Any
 
 import anyio
+import anyio.abc
 
 from mcp.shared.dispatcher import CallOptions, OnNotify, OnRequest, ProgressFnT
 from mcp.shared.exceptions import MCPError, NoBackChannelError
@@ -101,10 +102,17 @@ async def notify(self, method: str, params: Mapping[str, Any] | None) -> None:
             raise RuntimeError("DirectDispatcher has no peer; use create_direct_dispatcher_pair()")
         await self._peer._dispatch_notify(method, params)
 
-    async def run(self, on_request: OnRequest, on_notify: OnNotify) -> None:
+    async def run(
+        self,
+        on_request: OnRequest,
+        on_notify: OnNotify,
+        *,
+        task_status: anyio.abc.TaskStatus[None] = anyio.TASK_STATUS_IGNORED,
+    ) -> None:
         self._on_request = on_request
         self._on_notify = on_notify
         self._ready.set()
+        task_status.started()
         await self._closed.wait()
 
     def close(self) -> None:

src/mcp/shared/dispatcher.py

@@ -20,6 +20,7 @@
 from typing import Any, Protocol, TypedDict, TypeVar, runtime_checkable
 
 import anyio
+import anyio.abc
 
 from mcp.shared.transport_context import TransportContext
 
@@ -136,11 +137,21 @@ class Dispatcher(Outbound, Protocol[TransportT_co]):
     receive loop, per-request concurrency, and cancellation/progress wiring.
     """
 
-    async def run(self, on_request: OnRequest, on_notify: OnNotify) -> None:
+    async def run(
+        self,
+        on_request: OnRequest,
+        on_notify: OnNotify,
+        *,
+        task_status: anyio.abc.TaskStatus[None] = anyio.TASK_STATUS_IGNORED,
+    ) -> None:
         """Drive the receive loop until the underlying channel closes.
 
         Each inbound request is dispatched to ``on_request`` in its own task;
         the returned dict (or raised ``MCPError``) is sent back as the response.
         Inbound notifications go to ``on_notify``.
+
+        ``task_status.started()`` is called once the dispatcher is ready to
+        accept ``send_request``/``notify`` calls, so callers can use
+        ``await tg.start(dispatcher.run, on_request, on_notify)``.
         """
         ...