Error in SseMcpToolAdapter.from_server_params shows Server error '502 Bad Gateway' for url #6382
Description
What happened?
Describe the bug
I get an error when I use SseMcpToolAdapter to apply excel-mcp-server, it shows "httpx.HTTPStatusError: Server error '502 Bad Gateway' for url 'http://localhost:8088/sse'"
I think this is a bug because when I using VSCODE+CLINE, it works. Then I think the connection is OK.
But in Autogen, it fails.
Full errors as below:
- Exception Group Traceback (most recent call last):
| File "E:\Work\AI\APEXBOT\autogen_mcp_1.py", line 110, in
| asyncio.run(main_excel())
| File "C:\Users\Omar\anaconda3\Lib\asyncio\runners.py", line 194, in run
| return runner.run(main)
| ^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\asyncio\runners.py", line 118, in run
| return self._loop.run_until_complete(task)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\asyncio\base_events.py", line 687, in run_until_complete
| return future.result()
| ^^^^^^^^^^^^^^^
| File "E:\Work\AI\APEXBOT\autogen_mcp_1.py", line 53, in main_excel
| tools = await SseMcpToolAdapter.from_server_params(server_params, "excel")
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\site-packages\autogen_ext\tools\mcp_base.py", line 105, in from_server_params
| async with create_mcp_server_session(server_params) as session:
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\contextlib.py", line 210, in aenter
| return await anext(self.gen)
| ^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\site-packages\autogen_ext\tools\mcp_session.py", line 26, in create_mcp_server_session
| async with sse_client(**server_params.model_dump()) as (read, write):
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\contextlib.py", line 210, in aenter
| return await anext(self.gen)
| ^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\site-packages\mcp\client\sse.py", line 43, in sse_client
| async with anyio.create_task_group() as tg:
| ^^^^^^^^^^^^^^^^^^^^^^^^^
| File "C:\Users\Omar\anaconda3\Lib\site-packages\anyio_backends_asyncio.py", line 772, in aexit
| raise BaseExceptionGroup(
| ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)
+-+---------------- 1 ----------------
| Traceback (most recent call last):
| File "C:\Users\Omar\anaconda3\Lib\site-packages\mcp\client\sse.py", line 53, in sse_client
| event_source.response.raise_for_status()
| File "C:\Users\Omar\anaconda3\Lib\site-packages\httpx_models.py", line 829, in raise_for_status
| raise HTTPStatusError(message, request=request, response=self)
| httpx.HTTPStatusError: Server error '502 Bad Gateway' for url 'http://localhost:8088/sse'
For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/502
+------------------------------------
To Reproduce
Full code as below:
from autogen_ext.tools.mcp import SseMcpToolAdapter, SseServerParams
async def main_excel() -> None:
# Create server params for the remote MCP service
server_params = SseServerParams(
url="http://localhost:8088/sse",
)
# Get the translation tool from the server
tools = await SseMcpToolAdapter.from_server_params(server_params, "excel")
if __name__ == "__main__":
asyncio.run(main_excel())
Expected behavior
I think it should be execute successfully.
Screenshots
VScode + Cline: Works successfully.
MCP Configuration
VSCode+Cline+excle_mcp_server：Test successfully
excel_mcp_server: Works
Additional context
Add any other context about the problem here.
Which packages was the bug in?
Python Core (autogen-core), Python Extensions (autogen-ext)
AutoGen library version.
Python dev (main branch)
Other library version.
No response
Model used
No response
Model provider
None
Other model provider
No response
Python version
3.12
.NET version
None
Operating system
Windows