Fetch is failing with argument mismatch

[robotdad]

Describe the bug
Fetch is not working with the error below seen in the chat, there are no log messages.

To Reproduce
Steps to reproduce the behavior:

1. Configure fetch as described in the readme with uvx

I'm on Windows if that matters.

Additional context
This is the result from fetch:

{
  `url`: `https://github.com/modelcontextprotocol/servers/tree/main/src/memory`
}
McpError.__init__() takes 2 positional arguments but 3 were given

I did try the workaround in #65 but it had no impact on the behavior.

[allenporter]

Likely related to or fixed by modelcontextprotocol/python-sdk#116 so perhaps the newer python-sdk version would address. (I didn't follow the code path, just replying on mobile)

[xu-shaojie]

same problem,what about now?

[edisontim]

Any updates on this? I've installed the fetch server with uvx but the PR you've mentioned either isn't included yet or doesn't do the trick @allenporter

[allenporter]

@edisontim my impression is the fix for this landed in the mcp library version 1.2.0 (release notes). Can you check your mcp version and see if that resolves it? If not, then including a larger log entry with the stack trace would be helpful.

[alezkv]

There are changes in MCP version 1.1.3: modelcontextprotocol/python-sdk@b89cabc, which modified the initialization of McpError.

PR #507 should resolve this problem.

As a temporary workaround, you can use mcp==1.1.2 by running the following command:

uvx --with "mcp==1.1.2" mcp-server-fetch