Release v0.25.2 · ccf/agentcairn

The MCP server no longer fails to start on a fresh install (#152).
mcp was pinned as >=1.26.0 with no upper bound, so once the SDK published 2.0.0 — which removed
mcp.server.fastmcp (renamed to mcp.server.mcpserver) — uvx/uv resolved the new major and
cairn.mcp.server died on import with ModuleNotFoundError: No module named 'mcp.server.fastmcp'.

This broke every fresh uvx agentcairn run and both the Claude Code and Codex plugins, while
existing installs with a warm uv cache kept working — which is why it went unnoticed. CI could not
catch it either, because it runs uv run --locked against a lockfile pinning mcp 1.28.1; the locked
resolution is not what users get.

The dependency is now bounded to >=1.26.0,<2.0.0. Migrating to the 2.x API (and widening the
bound) is tracked separately.

If you hit this, just upgrade — no workaround needed anymore. The previously required
uvx --with 'mcp<2.0.0' agentcairn is no longer necessary.

Thanks to @fernandomartineztax-pixel for a precise report with a confirmed workaround.

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