The body is a lean ~14 lines with no concept-explanation padding; every line is directive and assumes Claude's competence, so each token earns its place.

It gives concrete, specific guidance: table-driven Go tests, named subsystems (parser, validator, projection, graph, source connector), enumerated security boundary categories, and real commands (`-count=1 -v`, `make verify`).

The five-step instruction list is clearly sequenced and includes an explicit verification step (`-count=1 -v` then `make verify`) plus a Success Criteria that asserts the test fails against unfixed behavior, providing a feedback checkpoint.

The skill is under 50 lines, needs no external references, and is organized into clean ## Instructions and ## Success Criteria sections, satisfying the simple-skill allowance for a top progressive-disclosure score.

The description names the domain ("Cerebro review findings, bugs, and security edge cases") and an action ("Add focused regression coverage"), but relies on a single verb rather than listing multiple distinct concrete actions, so it stops short of the top anchor.

It states what the skill does ("Add focused regression coverage...") but provides no "Use when..." clause or equivalent explicit trigger guidance, so the "when" dimension is only implied and is capped at 2 per the rubric guidelines.

Terms like "regression coverage", "bugs", and "security edge cases" are domain-relevant and would plausibly be said by a user, but common natural variations such as "test" or "regression test" are absent, leaving coverage incomplete.

The Cerebro-specific scoping gives it a clear niche, but without explicit trigger phrases it could still overlap with general testing skills, so it does not reach the clearly-distinguishable top anchor.