modelcontextprotocol
How to close the client connection correctly?
INFO: 127.0.0.1:52574 - "DELETE /mcp/ HTTP/1.1" 200 OK
[05/28/25 12:07:55] INFO HTTP Request: POST http://127.0.0.1:10003/mcp "HTTP/1.1 307 Temporary Redirect" _client.py:1740
INFO HTTP Request: POST http://127.0.0.1:10003/mcp "HTTP/1.1 307 Temporary Redirect" _client.py:1740
INFO HTTP Request: POST http://127.0.0.1:10003/mcp/ "HTTP/1.1 200 OK" _client.py:1740
INFO Received session ID: cfd7fba8487740b3b3e7f87a780633c7 streamable_http.py:140
ERROR Error parsing SSE message: streamable_http.py:173
ERROR Error reading SSE stream: streamable_http.py:321
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────── Traceback (most recent call last) ───────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ D:\ProgramData\sourcecode\agent.venv\Lib\site-packages\mcp\client\streamable_http.py:162 in _handle_sse_event │
│ │
│ 159 │ │ │ │ │ message.root.id = original_request_id │
│ 160 │ │ │ │ │
│ 161 │ │ │ │ session_message = SessionMessage(message) │
│ ❱ 162 │ │ │ │ await read_stream_writer.send(session_message) │
│ 163 │ │ │ │ │
│ 164 │ │ │ │ # Call resumption token callback if we have an ID │
│ 165 │ │ │ │ if sse.id and resumption_callback: │
│ │
│ D:\ProgramData\sourcecode\agent.venv\Lib\site-packages\anyio\streams\memory.py:242 in send │
│ │
│ 239 │ │ """ │
│ 240 │ │ await checkpoint() │
│ 241 │ │ try: │
│ ❱ 242 │ │ │ self.send_nowait(item) │
│ 243 │ │ except WouldBlock: │
│ 244 │ │ │ # Wait until there's someone on the receiving end │
│ 245 │ │ │ send_event = Event() │
│ │
│ D:\ProgramData\sourcecode\agent.venv\Lib\site-packages\anyio\streams\memory.py:213 in send_nowait │
│ │
│ 210 │ │ if self._closed: │
│ 211 │ │ │ raise ClosedResourceError │
│ 212 │ │ if not self._state.open_receive_channels: │
│ ❱ 213 │ │ │ raise BrokenResourceError │
│ 214 │ │ │
│ 215 │ │ while self._state.waiting_receivers: │
│ 216 │ │ │ receive_event, receiver = self._state.waiting_receivers.popitem(last=False) │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
BrokenResourceError
During handling of the above exception, another exception occurred:
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────── Traceback (most recent call last) ───────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ D:\ProgramData\sourcecode\agent\.venv\Lib\site-packages\mcp\client\streamable_http.py:307 in _handle_sse_response │
│ │
│ 304 │ │ try: │
│ 305 │ │ │ event_source = EventSource(response) │
│ 306 │ │ │ async for sse in event_source.aiter_sse(): │
│ ❱ 307 │ │ │ │ is_complete = await self._handle_sse_event( │
│ 308 │ │ │ │ │ sse, │
│ 309 │ │ │ │ │ ctx.read_stream_writer, │
│ 310 │ │ │ │ │ resumption_callback=( │
│ │
│ D:\ProgramData\sourcecode\agent\.venv\Lib\site-packages\mcp\client\streamable_http.py:174 in _handle_sse_event │
│ │
│ 171 │ │ │ │
│ 172 │ │ │ except Exception as exc: │
│ 173 │ │ │ │ logger.error(f"Error parsing SSE message: {exc}") │
│ ❱ 174 │ │ │ │ await read_stream_writer.send(exc) │
│ 175 │ │ │ │ return False │
│ 176 │ │ else: │
│ 177 │ │ │ logger.warning(f"Unknown SSE event: {sse.event}") │
│ │
│ D:\ProgramData\sourcecode\agent\.venv\Lib\site-packages\anyio\streams\memory.py:242 in send │
│ │
│ 239 │ │ """ │
│ 240 │ │ await checkpoint() │
│ 241 │ │ try: │
│ ❱ 242 │ │ │ self.send_nowait(item) │
│ 243 │ │ except WouldBlock: │
│ 244 │ │ │ # Wait until there's someone on the receiving end │
│ 245 │ │ │ send_event = Event() │
│ │
│ D:\ProgramData\sourcecode\agent\.venv\Lib\site-packages\anyio\streams\memory.py:213 in send_nowait │
│ │
│ 210 │ │ if self._closed: │
│ 211 │ │ │ raise ClosedResourceError │
│ 212 │ │ if not self._state.open_receive_channels: │
│ ❱ 213 │ │ │ raise BrokenResourceError │
│ 214 │ │ │
│ 215 │ │ while self._state.waiting_receivers: │
│ 216 │ │ │ receive_event, receiver = self._state.waiting_receivers.popitem(last=False) │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
BrokenResourceError
---------------------------------error INFO HTTP Request: POST http://127.0.0.1:10003/mcp/ "HTTP/1.1 400 Bad Request" _client.py:1740 ERROR Error in post_writer: Client error '400 Bad Request' for url 'http://127.0.0.1:10003/mcp/' streamable_http.py:404 For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/400
client running call_toos, waiting the response, and the client closes the connection, but it fails. How to close the connection correctly？ mcp version is 1.9.1 thanks!
