MCP error -32603: Internal error

[kiliankoe]

Hi, this project looks fascinating! On trying it out, all I'm running into unfortunately is MCP error -32603: Internal error. I see that this appears to be a JSON RPC error, but I'm very unsure about what exactly this is stumbling up on.

The list of tools is fine in both the MCP inspector and Claude Desktop.

The tools/call request, however, made through emcee never makes it to the actual API, could this be an error in my spec? Clients generated from it are fine, though.

[mattt]

Hi @kiliankoe. Thanks for taking a look at emcee!

Can you share a link to the OpenAPI spec you're using? (Assuming its public; no worries if not)

[kiliankoe]

Hey @mattt, one version of the spec is here: https://portal.wandelbots.io/docs/api/v1/ui/public.openapi.yaml

I'm specifically running emcee against the spec from a separate (unfortunately non-public) host, though. One that actually allows requests. The public shareable version just functions as documentation in that regard, unfortunately.

[spectrumvoip-stefano]

I've also been having this same error message appear for a different openapi spec. Looking for ways to debug this.

[mattt]

@kiliankoe @spectrumvoip-stefano I just merged #58, which replaces our original, hand-rolled implementation of MCP with the official Go SDK. I suspect this will fix a bunch of underlying problems.

Can you please retry with the latest version and let me know if you're still seeing this?

[kiliankoe]

Hey @mattt, thanks for the update! I just tried it again, and it appears to be working! 🥳 I'll go ahead and close this :)

[mattt]

Thanks for verifying, @kiliankoe! Really glad to hear that everything's working as expected now 😌