Conciseness

The ~90-line body is dense instruction with no explanations of concepts Claude already knows: every line is a step, a judgment rule, a concrete example, or output format. It leans on Claude's competence (e.g. "Review a change like the senior developer who will be paged when it breaks") with every token earning its place, matching anchor 5.

Actionability

Guidance is fully executable for an instruction-only skill: concrete steps ("grep every caller", "say which load you assumed"), enumerated finding categories with specific instances (check-then-write races, O(n^2), a query per item), exact output templates ("Verdict: Ship.", "Lean: -<N> lines possible."), and a complete worked example finding containing all four parts with a copy-paste fix. Per the scoring notes, absence of code is not penalized when guidance is this actionable — anchor 5.

Workflow Clarity

The body lays out a clear four-phase sequence (Understand first → Look for → Check before you report → Output) with an explicit validation checkpoint: "Re-read the lines and confirm: the caller exists, the value can really be empty, the code really is unused" and "No case, no finding". This matches anchor 5's explicit validation steps and checklist; the destructive/batch cap does not apply since the skill explicitly changes no code.

Progressive Disclosure

The body is well-organized into four clearly numbered sections with no bundle files and no dead-end references, and all content is core guidance that arguably belongs inline. However, at ~92 lines it exceeds the under-50-line simple-skill exception, and supporting material such as the worked example finding or the category definitions could live in a one-level-deep reference file — anchor 4 rather than 5.

Specificity

The description enumerates concrete review areas ("bugs, security, real load, missing tests, speed, and what to delete") and specifies the finding format ("Each finding says what goes wrong and how to fix it"), matching anchor 4's several specific actions with minor gaps. It is not a 5 because the only action verb is 'review' — the enumerated items are focus areas rather than a comprehensive list of concrete actions.

Completeness

The 'what' is clear and concrete (quality review of a diff across six named dimensions with a defined finding format), but there is no 'Use when...' clause or equivalent explicit trigger guidance; the 'when' is only weakly implied by 'of a diff'. Per the judging guideline, a missing 'Use when' clause caps completeness at 3.

Trigger Term Quality

Terms like "review", "diff", "bugs", "security", "missing tests", and "speed" are natural user phrasings for requesting this skill, giving good keyword coverage (anchor 4). Common variations such as "code review", "PR", or "pull request" are absent, keeping it below anchor 5's comprehensive synonym/extension coverage.

Distinctiveness Conflict Risk

"Quality review of a diff" plus the distinctive lean/delete emphasis ("what to delete") carves a mostly distinct niche with minimal trigger confusion, matching anchor 4. It is not a 5 because it overlaps with generic code-review skills that would trigger on the same 'review my diff' phrasing.