alt Hacker NewsThe prod-readiness concerns are fair, but mcp-use fills a real gap in the MCP stack: orchestration across many servers with far less boilerplate than the official SDK. Even if the agent is as another commenter fairly pointed out, just a LangChain wrapper, the six-line setup and server manager are a nice DX upgrade.
What’s still missing is structured error semantics. Right now, when a tool explodes the LLM only sees a raw stack trace, so it can’t decide whether to retry or bail. Today, I saw another Show HN post on MCP here: https://news.ycombinator.com/item?id=44778968 which converts exceptions into a small JSON envelope (error, details, isRetryable, etc.) that agents can interpret. Dropping that into mcp-use’s client loop would give you observability + smarter retries for almost free.
I might be missing some important nuances here between client side and server side MCP error handling, which I’ll leave to the authors to discuss. Just thought there might be a good open source collab opportunity here.
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Hey thanks for the comment, the work from https://github.com/bjoaquinc/mcp-error-formatter is great. I will definitely put some version of this into one of the next releases. Just opened an issue mentioning this thread.
The problem with the package above is that it is server side, and I think it should be. Server is the one that knows (has responsibility to know) if a tool is retryable and has informations about the error, and fairly so.
I see though how some sort of improved error formatting could be introduced in the client as well, but it shouldn't contain any logic about the error, rather format the error in the best way possible (in the direction in which it is best understandable by LLMs).
Thanks for the mention! I'm the author of Mcp-error-formatter, which was mentioned above. Exactly right about the client/server complexity. I've been working on this exact problem. Client-side heuristics can catch timeouts and HTTP codes, but nuanced business logic errors need server cooperation.
The interesting part is dual error representation: devs need full stack traces for debugging, but LLMs need clean structured metadata for retry decisions. Plus you want error telemetry flowing to observability systems.
Question for the mcp-use authors: How do you handle error propagation in multi-server setups? If Server A times out but Server B is healthy, does the agent know which server failed and whether to retry or switch servers? And are you capturing error patterns to identify flaky servers or consistently failing tool calls? The retry orchestration across multiple MCP servers seems like a really interesting problem.