fix(mcp): pin mcp<2 — an unbounded floor let CI install a breaking major - #2
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`dependencies = ["mcp>=1.0.0"]` had no upper bound, so CI installed mcp 2.0.0 as soon as it shipped. The server imports `mcp.server.fastmcp`, which 2.x no longer exposes at that path, and the `mcp` job started failing with ModuleNotFoundError. Nothing in this repo changed — the dependency did. main has not re-run CI since 2026-07-22, so the rot only surfaced when a PR triggered the workflow. Pin to `>=1.0.0,<2` to restore a working install. Supporting 2.x is a separate change: it needs the new import path, so the bound should be lifted together with it, not before. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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What broke
mcp/pyproject.tomldeclaredmcp>=1.0.0with no upper bound, so CI installed mcp 2.0.0as soon as it shipped. The server imports
mcp.server.fastmcp, which 2.x no longer exposes atthat path:
Nothing in this repo changed — the dependency did.
mainhas not re-run CI since 2026-07-22,so the breakage sat there unseen and only surfaced when an unrelated PR triggered the workflow.
The fix
Pin to
>=1.0.0,<2to restore a working install. Verified the specifier admits 1.0.0 / 1.27.2 /1.29.0 and excludes 2.0.0.
Supporting 2.x is deliberately not in this PR: it needs the new import path, so the bound
should be lifted together with that change rather than before it. The comment in the file says so,
to keep the next person from widening it on reflex.
Scope
One file, one dependency line (plus the explanatory comment). No behavior change.
🤖 Generated with Claude Code