Fix unstructured tool errors being masked as 'outputSchema defined but no structured output returned'#781

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jairus-m merged 3 commits into

mainfrom

bug/output-validation-error

May 19, 2026

Commits on May 15, 2026

Fix unstructured tool errors being masked as 'outputSchema defined but no structured output returned'
jairus-m
committed
Raise error instead of return CallToolResult to maintain FastMCP.call_tool return types (error gets propfated and caught by FastMCP's handler)
jairus-m
committed
Update unit tests to raise instead of CallToolResult from original commit
jairus-m
committed