check
Read-only drift detector. Diffs SPEC.md against current code and reports violations grouped by severity. Writes nothing — suggests remedies via the spec or build skills but never invokes them. Triggers when the user asks to check drift, audit the spec, verify invariants, or ask whether code still matches the spec. Phrasings: "check drift", "audit the spec", "does the code still match §V", "check invariants", "spec vs code".
npx skills add JuliusBrussee/cavekit --skill check --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# check — drift report Pure diagnostic. Reports violations. Writes nothing. User decides remedy. Spec drifting silently from code is the #1 SDD failure mode. check is the detector. Run it after each `/build` and before each ship — drift caught here is a diff; drift caught in prod is a §B. ## LOAD 1. Read `SPEC.md`. If missing → "no spec, nothing to check." Stop. 2. Parse invocation args: - `§V` → check invariants only (default) - `§I` → check interfaces - `§T` → audit task status vs code - `--all` → all three ## CHECK §V — invariants For each V<n>: 1. Translate invariant into verifiable claim about code. 2. Grep / read relevant files. 3. Classify: **HOLD** / **VIOLATE** / **UNVERIFIABLE**. 4. Record address + file:line evidence. ## CHECK §I — interfaces For each I item: 1. Locate implementation. 2. Classify: - **MATCH** — shape in code = shape in spec. - **DRIFT** — impl exists, shape differs. - **MISSING** — impl absent. - **EXTRA** — code exposes surface not in §I. ## CHECK §T — tasks For each T<n>: 1. If `x`: verify claimed work present. 2. If `~`: note as in-progress. 3. If `.`: note as pending. 4. Flag `x` rows with no evidence as **STALE**. ## REPORT Caveman. Grouped by sever
- LOAD
- CHECK §V — invariants
- CHECK §I — interfaces
- CHECK §T — tasks
- REPORT
- REMEDY HINTS (not actions)
- NON-GOALS
What does the check skill do?
Read-only drift detector. Diffs SPEC.md against current code and reports violations grouped by severity. Writes nothing — suggests remedies via the spec or build skills but never invokes them. Triggers when the user asks to check drift, audit the spec, verify invariants, or ask whether code still matches the spec. Phrasings: "check drift", "audit the spec", "does the code still match §V", "check invariants", "spec vs code".
How do I install it?
Run `npx skills add JuliusBrussee/cavekit --skill check --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From JuliusBrussee/cavekit, a repository with 1,133 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.