Extract tool parameter descriptions from docstrings - #2876
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FastMCP/MCPServer ignored per-parameter documentation in function docstrings, so generated tool JSON schemas had empty parameter descriptions. Parse Google, NumPy, and Sphinx style docstrings via griffe and populate each parameter's description in the schema. Explicit Annotated[T, Field(description=...)] still takes precedence, and functions without docstrings are unaffected. Closes modelcontextprotocol#226
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Implements #226 — green and ready for review |
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Thanks for the PR. Per our CONTRIBUTING.md we ask that PRs start from a linked, triaged issue with maintainer buy-in, which this one doesn't have yet. Closing as part of a general backlog cleanup following the v2 release. If this is still relevant against v2, feel free to reopen. |
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FastMCP/MCPServer previously ignored per-parameter documentation in function docstrings, so generated tool JSON schemas had empty parameter descriptions. This parses Google, NumPy, and Sphinx style docstrings via griffe and populates each parameter's description in the schema.
Explicit Annotated[T, Field(description=...)] still takes precedence, and functions without docstrings are unaffected.
Closes #226
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