Use when writing or designing code: name premise and blast radius, deepen modules at seams, TDD at agreed seams, diagnose before patching, and keep producer→consumer contracts honest.
Use when premises or options must be pressure-tested, a short plan/handoff is needed, or a large plan must be sliced — grill facts locally, ask decisions one at a time.
Use when a project needs a lean `.do-it/handbook/` for stable project truth plus `.do-it/worklog/` for daily or goal notes.
Use before any done, fixed, passing, ready, install, or merge claim, and when closing a branch — fresh evidence on this worktree; hooks vary by host, this skill is the checklist.
Use only when the user explicitly asks to enable, disable, inspect, report, or persist opt-in local do-it behavioral feedback.
Use when starting any non-trivial repo task: pick Light / Standard / Heavy tier, then self-select meaning skills — not a fixed pipeline.
Use when repo terms or invariants are drifting, or when user/docs/code naming disagrees and a canonical glossary is needed — `.do-it/CONTEXT.md` is the downstream source of truth for names, relationships, and facts.
Use when creating or updating do-it skills: write predictable model-invoked descriptions, progressive disclosure, leading words, and hook-aware escape behavior.