feat(launch): lazy-MCP loading with opt-in prune (profile + global)#90
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Prune a profile's MCP servers to what its skills actually need so unused tool
schemas don't burn always-on context. Interactive launches keep the existing
opt-out picker + remembered per-dir overrides; non-interactive launches stay
fail-open (keep all) unless CUE_PRUNE_MCPS opts in:
CUE_PRUNE_MCPS=auto drop unused PROFILE-declared MCPs (user-global MCPs
stay untouched — the existing tested invariant holds)
CUE_PRUNE_MCPS=all also drop unused GLOBAL servers present in the runtime
.claude.json (heavy ones a coding profile never calls);
a louder opt-in because it removes globally-set config
Precedence: --disable-mcp > remembered override > CUE_PRUNE_MCPS > keep-all.
disabledMcpIds (incl globals under =all) flow to the materializer, which evicts
exactly those keys from .claude.json and never touches an unnamed user MCP.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…t hermetic Two CI failures vs main, both from entanglement — neither is the lazy-MCP feature: 1. runtime-materializer.ts had an unrelated proxy health-probe rewrite (TCP-connect → HTTP /health) swept in from branch WIP, but its matching test update lived in a file this PR doesn't carry. Reverted the probe to main's TCP-connect version (keeping all lazy-MCP changes: disabledMcpIds plumbing + syncMcpsIntoClaudeJson). Restores `import net`, drops the now unused http/https imports. 2. skill-dependencies.getNeeded.test.ts was an integration test against the live resources/skills submodule, asserting requires_mcps backfills not present on main's pinned submodule commit. Added an optional skillsRoot param to getNeededMcps/getSkillDependencies/findSkillContent (default unchanged) and rewrote the test to use hermetic temp fixtures covering every detection path (inline + block-sequence requires_mcps, implicit body ref, no-dep, unknown id). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…e (review M-1) Review flagged that `--disable-mcp <id>` set reviewed=true, so the choice was written as a remembered per-dir override and silently stuck on every later launch until `--cue-pick-mcps`. The flag's doc reads one-shot, and a CI or debug run must not pollute a shared checkout with override files. Apply the disable for this launch only; persist a choice via the interactive picker. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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What
Prune a profile's MCP servers down to what its skills actually need, so unused tool schemas don't burn always-on context every message. Pairs with the honest MCP token accounting from #88 (which can now prove the saving via
cue cost).Behavior
mcp-picker.ts) + remembered per-dir overrides (mcp-overrides.ts).CUE_PRUNE_MCPSopts in:CUE_PRUNE_MCPS=auto— drop unused profile-declared MCPs only (user-global MCPs stay untouched — preserves cue's existing invariant).CUE_PRUNE_MCPS=all— also drop unused global servers present in the runtime.claude.json(heavy ones a coding profile never calls). Louder opt-in: it removes globally-set config.--disable-mcp> remembered override >CUE_PRUNE_MCPS> keep-all.pin: trueon a profile MCP marks it agent-core (never pruned).disabledMcpIdsflow to the materializer, which evicts exactly those keys from.claude.jsonand never touches an unnamed user MCP.Merge note
This unions cleanly with main's newer
when:conditional-MCP feature: the MCP ref schema/types now carry bothwhen(activation gate) andpin(prune-exempt) — seeprofiles/schema.jsonMcpRefandprofiles/_types.ts.Test plan
bunx tsc --noEmit— clean (the when+pin union compiles)bun teston mcp-overrides / mcp-picker / skill-dependencies.getNeeded / runtime-materializer.mcp-prune / profile-loader — pass (CI checks outsubmodules: recursive)🤖 Generated with Claude Code