[codex] Prevent MCP tool metadata hangs on malformed responses#110
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zoeshawwang wants to merge 1 commit into
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[codex] Prevent MCP tool metadata hangs on malformed responses#110zoeshawwang wants to merge 1 commit into
zoeshawwang wants to merge 1 commit into
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Constraint: MCP Python client can log malformed JSON-RPC errors without waking pending initialize/list_tools awaits. Rejected: Template-side timeout only | leaves SDK callers exposed to the same hang. Confidence: high Scope-risk: narrow Directive: Keep MCP metadata operations bounded so agent creation cannot wait indefinitely on malformed server responses. Tested: uv run ruff check agentrun/tool/api/mcp.py tests/unittests/tool/test_mcp.py; uv run pytest tests/unittests/tool/test_mcp.py -q; uv run pytest tests/unittests/tool -q; git diff --check Not-tested: live MCP server returning malformed JSON-RPC error Closes: coop#82638110 Change-Id: I20569d10af7ba44c140ab19e446d7fc35870f7ec
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Summary
Fixes an AgentRun SDK hang where ToolResource MCP metadata loading can wait indefinitely when the MCP Python transport logs a malformed JSON-RPC response, for example an error payload with
error.message = null.Aone: https://project.aone.alibaba-inc.com/v2/project/2139638/req/82638110
Root Cause
The MCP Python streamable HTTP transport can surface malformed JSON-RPC response parsing as an
Exceptionon the read stream. The defaultClientSessionhandler does not route that exception back to the pendinginitializeorlist_toolsrequest, so SDK callers can keep awaiting forever.Changes
initializeandlist_tools) with a 30s timeout so agent creation cannot hang indefinitely on malformed or silent MCP responses.Config.timeoutso tool calls also fail instead of waiting forever.Validation
uv run ruff check agentrun/tool/api/mcp.py tests/unittests/tool/test_mcp.pyuv run pytest tests/unittests/tool/test_mcp.py -quv run pytest tests/unittests/tool -qgit diff --checkNotes
The MCP service should still be fixed to return a valid JSON-RPC error with a string
error.message; this SDK change prevents the client-side hang while preserving that server-side requirement.