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fix: skip oneOf outputSchema injection for MCP client compatibility - #169
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MCP clients (e.g. Inspector) require outputSchema to have "type": "object" at top level. Tools with multi-shape responses (plan_status, plan_file_info) use oneOf which clients reject with validation errors. Skip injecting these schemas so the tools work without an advertised outputSchema. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
oneOfoutput schemas into FastMCP tools — MCP clients (e.g. Inspector) requireoutputSchemato have"type": "object"at top level and rejectoneOfplan_status,plan_file_info) work correctly without an advertised schema sincestructuredContentis always setTest plan
test_tool_surface_consistency.py,test_http_utils.py,test_plan_file_info_tool.py)test_fastmcp_oneof_tools_have_no_output_schemaverifies oneOf schemas are not advertisedtest_fastmcp_flat_tools_use_canonical_output_schemaverifies flat schemas are still injectedtools/listin MCP Inspector returns no validation errors🤖 Generated with Claude Code