fix: bump MCP SDK to >=1.23.0 for protocol 2025-11-25 support#118
Merged
Wh1isper merged 1 commit intoai-zerolab:mainfrom Feb 14, 2026
Merged
fix: bump MCP SDK to >=1.23.0 for protocol 2025-11-25 support#118Wh1isper merged 1 commit intoai-zerolab:mainfrom
Wh1isper merged 1 commit intoai-zerolab:mainfrom
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Claude Desktop now requires MCP protocol version 2025-11-25, but mcp v1.16.0 only supports 2025-06-18. This causes Claude Desktop to silently refuse to expose tools despite a successful handshake. Bumps mcp[cli] from >=1.3.0 to >=1.23.0,<2 (resolves to v1.26.0). The <2 upper bound avoids upcoming v2 breaking changes per upstream SDK guidance. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
mcp[cli]from>=1.3.0to>=1.23.0,<2(resolves to v1.26.0)2025-11-25, but mcp v1.16.0 only supports2025-06-18<2upper bound avoids upcoming v2 breaking changes per upstream SDK guidanceContext
Despite a fully successful MCP handshake (server starts,
tools/listreturns 20+ tools), Claude Desktop silently refuses to expose the tools in conversations when the protocol version doesn't match. The server responds withprotocolVersion: "2025-06-18"but the client expects2025-11-25.v1.23.0 of the Python MCP SDK introduced support for protocol
2025-11-25.What changed
One line in
pyproject.toml:Plus the regenerated
uv.lock(mcp resolves from 1.16.0 → 1.26.0).No source code changes. The project only imports
FastMCPand uses@mcp.tool()/mcp.run()— all stable APIs across this version range.Test plan
uv lock && uv syncsucceeds (mcp 1.16.0 → 1.26.0)uv run pytest tests/ -v— all 130 tests pass🤖 Generated with Claude Code