mcp: treat pointers equivalently to non-pointers when deriving schema #338
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This is thorough. But it won't merge at all after #325. I gutted newServerTool. |
As reported in modelcontextprotocol#199 and modelcontextprotocol#200, the fact that we return a possibly "null" schema for pointer types breaks various clients, which expect schemas to be of type "object". This is an unfortunate footgun. For now, assume that the user wants us to treat pointers equivalently to non-pointers. If we want to change this behavior in the future, we can do so behind an option. + a test Also fix the handling of nil results in the case where the output schema is non-nil: we must provide structured content in this case. (This was causing the test to fail). Fixes modelcontextprotocol#199 Fixes modelcontextprotocol#200
jba
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jba
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findleyr
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Some bad merging in modelcontextprotocol#338 led to a bad bug in the handling of structured output for pointer output types. Add a conformance test and fix the bug.
samthanawalla
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Some bad merging in #338 led to a bad bug in the handling of structured output for pointer output types. Add a conformance test and fix the bug.
yasomaru
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Aug 28, 2025
Some bad merging in modelcontextprotocol#338 led to a bad bug in the handling of structured output for pointer output types. Add a conformance test and fix the bug.
RatStar811
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Nov 19, 2025
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As reported in #199 and #200, the fact that we return a possibly "null" schema for pointer types breaks various clients, which expect schemas to be of type "object". This is an unfortunate footgun. For now, assume that the user wants us to treat pointers equivalently to non-pointers. If we want to change this behavior in the future, we can do so behind an option.
Also fix the handling of nil results in the case where the output schema is non-nil: we must provide structured content in this case. (This was causing the test to fail).
Fixes #199
Fixes #200