Use anyio.event

src/fastmcp/client/client.py

@@ -196,8 +196,8 @@ class Client(Generic[ClientTransportT]):
         self._nesting_counter: int = 0
         self._context_lock = anyio.Lock()
         self._session_task: asyncio.Task | None = None
-        self._ready_event = asyncio.Event()
-        self._stop_event = asyncio.Event()
+        self._ready_event = anyio.Event()
+        self._stop_event = anyio.Event()
 
     @property
     def session(self) -> ClientSession:

src/fastmcp/client/transports.py

@@ -18,6 +18,7 @@ from typing import (
     overload,
 )
 
+import anyio
 import httpx
 from mcp import ClientSession, StdioServerParameters
 from mcp.client.session import (
@@ -327,8 +328,8 @@ class StdioTransport(ClientTransport):
 
         self._session: ClientSession | None = None
         self._connect_task: asyncio.Task | None = None
-        self._ready_event = asyncio.Event()
-        self._stop_event = asyncio.Event()
+        self._ready_event = anyio.Event()
+        self._stop_event = anyio.Event()
 
     @contextlib.asynccontextmanager
     async def connect_session(
@@ -391,8 +392,8 @@ class StdioTransport(ClientTransport):
 
         # reset variables and events for potential future reconnects
         self._connect_task = None
-        self._stop_event = asyncio.Event()
-        self._ready_event = asyncio.Event()
+        self._stop_event = anyio.Event()
+        self._ready_event = anyio.Event()
 
     async def close(self):
         await self.disconnect()

tests/server/test_logging.py

@@ -2,6 +2,7 @@ import asyncio
 import logging
 from unittest.mock import AsyncMock, Mock, patch
 
+import anyio
 import pytest
 
 from fastmcp.server.server import FastMCP
@@ -27,7 +28,7 @@ async def test_uvicorn_logging_default_level(
     """Tests that FastMCP passes log_level to uvicorn.Config if no log_config is given."""
     mock_server_instance = AsyncMock()
     mock_uvicorn_server_constructor.return_value = mock_server_instance
-    serve_finished_event = asyncio.Event()
+    serve_finished_event = anyio.Event()
     mock_server_instance.serve.side_effect = serve_finished_event.wait
 
     test_log_level = "warning"
@@ -63,7 +64,7 @@ async def test_uvicorn_logging_with_custom_log_config(
     """Tests that FastMCP passes log_config to uvicorn.Config and not log_level."""
     mock_server_instance = AsyncMock()
     mock_uvicorn_server_constructor.return_value = mock_server_instance
-    serve_finished_event = asyncio.Event()
+    serve_finished_event = anyio.Event()
     mock_server_instance.serve.side_effect = serve_finished_event.wait
 
     sample_log_config = {
@@ -123,7 +124,7 @@ async def test_uvicorn_logging_custom_log_config_overrides_log_level_param(
     """Tests log_config precedence if log_level is also passed to run_http_async."""
     mock_server_instance = AsyncMock()
     mock_uvicorn_server_constructor.return_value = mock_server_instance
-    serve_finished_event = asyncio.Event()
+    serve_finished_event = anyio.Event()
     mock_server_instance.serve.side_effect = serve_finished_event.wait
 
     sample_log_config = {