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Empty mcp tool result error#1142
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seratch approved these changesJul 16, 2025
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This makes sense and looks good to me; thanks for sending this!
076eb72 intoopenai:main 5 checks passed
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Summary
Fixed
MCPUtil.invoke_mcp_tool()to return"[]"instead of logging an error when MCP tools return empty content. Empty results (None, []) are valid outputs and should be treated consistently withfunction tools. The
None -> "[]"and[] -> "[]"behavior comes from the MCP Python SDK's FastMCP implementation.Test plan
test_mcp_fastmcp_behavior_verification()that verifies all FastMCP edge casesNone, [], {}, [{}], [[]]cases correctlyIssue number
Closes#1035
Checks
make lintandmake format