fix(claude-code): pin mcp<2 so the MCP server can import FastMCP - #3027
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runbgp wants to merge 1 commit into
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fix(claude-code): pin mcp<2 so the MCP server can import FastMCP#3027runbgp wants to merge 1 commit into
runbgp wants to merge 1 commit into
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mcp 2.0.0 (PyPI, 2026-07-28) removed mcp.server.fastmcp, which scripts/mcp_server.py imports at module scope. Fresh venv bootstraps resolve 2.0.0 and the server exits on import, surfacing as -32000: Connection closed with no agent_knowledge_* tools.
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Fixes #3026.
mcp2.0.0 (2026-07-28) removedmcp.server.fastmcp, whichscripts/mcp_server.pyimports at module scope. Undermcp>=1.0.0, fresh venv bootstraps resolve 2.0.0 and the server exits on import — surfaced as-32000: Connection closedwith noagent_knowledge_*tools.Existing venvs are unaffected:
run_mcp.shre-pips only on cache drift orimport mcpfailure, and that still succeeds on 2.0.0. Only fresh installs break.<2resolves to 1.29.0. Verified on Python 3.14.4 — import works,run_mcp.shstarts and exits 0 on stdin close,claude mcp listreports connected.Same shape as #1641. Left the identical unbounded range in
claude-agent-sdkandhindsight-integration-testsalone; neither importsfastmcp, noted in the issue.