[Bug] The MCP service fails to run.

[a506488043]

What were you trying to accomplish?

8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:34,211 - INFO - Configuring MCP Servers: 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:34,212 - INFO - Enabling hot reload for config file: /mnt/256G/docker/servers/test.json 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:34,213 - INFO - Started watching config file: /mnt/256G/docker/servers/test.json 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:34,213 - INFO - Uvicorn server starting... 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: INFO: Started server process [54030] 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: INFO: Waiting for application startup. 8月 25 15:21:34 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:34,220 - INFO - Initiating connection for server: 'mcp-pandoc'... 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:36,011 - ERROR - Failed to connect to MCP server 'mcp-pandoc': ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: + Exception Group Traceback (most recent call last): 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcpo/main.py", line 422, in lifespan 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | async with client_context as (reader, writer, *_): 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/usr/lib/python3.12/contextlib.py", line 231, in __aexit__ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | await self.gen.athrow(value) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcp/client/stdio/__init__.py", line 180, in stdio_client 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | async with ( 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/anyio/_backends/_asyncio.py", line 772, in __aexit__ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | raise BaseExceptionGroup( 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: +-+---------------- 1 ---------------- 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | Exception Group Traceback (most recent call last): 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcp/client/stdio/__init__.py", line 187, in stdio_client 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | yield read_stream, write_stream 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcpo/main.py", line 423, in lifespan 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | async with ClientSession(reader, writer) as session: 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcp/shared/session.py", line 218, in __aexit__ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | return await self._task_group.__aexit__(exc_type, exc_val, exc_tb) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/anyio/_backends/_asyncio.py", line 772, in __aexit__ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | raise BaseExceptionGroup( 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: +-+---------------- 1 ---------------- 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | Traceback (most recent call last): 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcpo/main.py", line 425, in lifespan 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | await create_dynamic_endpoints(app, api_dependency=api_dependency) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcpo/main.py", line 271, in create_dynamic_endpoints 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | tools_result = await session.list_tools() 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | ^^^^^^^^^^^^^^^^^^^^^^^^^^ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcp/client/session.py", line 386, in list_tools 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | result = await self.send_request( 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | ^^^^^^^^^^^^^^^^^^^^^^^^ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | File "/root/.cache/uv/archive-v0/5JpOJOKIuKyAZE0ckdcas/lib/python3.12/site-packages/mcp/shared/session.py", line 286, in send_request 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | raise McpError(response_or_error.error) 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: | mcp.shared.exceptions.McpError: name 'false' is not defined 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: +------------------------------------ 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:36,013 - ERROR - Failed to establish connection for server: 'mcp-pandoc' - Multiple errors occurred: 8月 25 15:21:36 saiita-System-Product-Name uvx[54030]: 2025-08-25 15:21:36,013 - ERROR - Error 1: ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)

Expected Behavior

Failed to add/install the MCP service.

Actual Behavior

Failed to add/install the MCP service.

Environment Information

Operating System:

Ubuntu 24.04

Python Version:

Python 3.12.3

mcp-pandoc Version:

# Run: python -c "import mcp_pandoc; print(mcp_pandoc.__version__)"
# Or: pip show mcp-pandoc | grep Version

MCP Client:
mcpo

Steps to Reproduce

No response

Screenshots or Logs

No response

Pre-submission Checklist

• I have searched existing issues to avoid duplicates
• I have provided environment information requested above

[maccman]

Just came across this bug.

[JUJUup]

Also came across this bug. Checked in MCP inspector, connection to MCP service is good but cannot fetch tools, indicating:

"Error fetching tooIs:mcp-pandoc-MCp Server tools/list error: {'code': 0,'message': "name 'false' is not defined "

Quick fix: comment out "additionalProperties": false in /src/mcp_pandoc/server.py and install using source code (pip install .)

It works but Im not sure why it works...

[a506488043]

Also came across this bug. Checked in MCP inspector, connection to MCP service is good but cannot fetch tools, indicating:

"Error fetching tooIs:mcp-pandoc-MCp Server tools/list error: {'code': 0,'message': "name 'false' is not defined "

Quick fix: comment out "additionalProperties": false in /src/mcp_pandoc/server.py and install using source code (pip install .)

It works but Im not sure why it works...

It doesn't work for me following your method.

[vivekVells]

Thanks for reporting and helping track this down!

@JUJUup @a506488043 Quick update:

• The "additionalProperties": false bug is fixed in fix: false should be False #31 and released in [v0.8.1](https://pypi.org/project/mcp-pandoc/).
• Linting is now enforced via pre-commit and CI (details, and the latest CI run passed. Added CI batch in README.md as well.

@a506488043 Can you confirm if the issue’s resolved for you on v0.8.1? Let me know if you’re still seeing any problems.