Conciseness

The body is mostly efficient instruction with no explanation of concepts Claude already knows, but it repeats itself: the five-heading shape check appears three times (Step 0, mid-Step 4, and the final check section), the banned-heading list ("## Summary", "## Verdict", "## Scope and method", "## Bottom line") is stated twice nearly verbatim, and passages like "a run that leaves a differently-shaped file has produced nothing, however good the audit inside it" are rhetorical padding. It is above level 2 because every section still carries real, non-generic instruction rather than padded explanation.

Actionability

Guidance is fully executable and copy-paste ready: the `cat > TEST-REVIEW.md <<'EOF'` skeleton, `bun run --cwd <workspace-path> build` / `test:run` commands, the `ls`/`find` test-layout resolution, exact `grep -c` validation commands, and an exact four-field finding template. It matches the level-5 anchor — concrete commands and examples cover the common cases, exceeding level 4's 'minor gaps'.

Workflow Clarity

Steps 0–4 are explicitly sequenced with built-in validation checkpoints (`grep -c '^## ...'` must print 5, checked as soon as the first gap is written and again before finishing) and feedback loops (restore the five headings and re-edit; "No step is a stop" — a failing build or test is recorded under `## Not run` and the run continues). This matches the level-5 anchor with both explicit validation and error-recovery loops.

Progressive Disclosure

The single SKILL.md is well-sectioned with clear headers, and its two external pointers (`wiki/conventions/testing-patterns.md`, `wiki/conventions/browser-tests.md`) are one level deep and clearly signaled in context. It is not level 5 because at ~207 lines it is a monolithic file with no bundle — the finding-format and report-shape detail could live in a reference file; it is above level 3 because structure and signaling are good and nothing is buried.

Specificity

The description lists multiple concrete actions spanning the full pipeline — "building and running the affected workspaces", "auditing changed code for missing test files, untested exports, untested error paths and untested routes", and "reporting gaps with T-M/U/E/R/S IDs" — with comprehensive coverage of the skill's domain. It exceeds the level-4 anchor because there are no minor gaps in action coverage, not even extensions or peripheral tasks left unnamed.

Completeness

It explicitly answers both halves: "Use when checking whether a branch is adequately tested" gives a concrete when-clause, and the rest of the sentence fully states what the skill does (build, run, audit four gap types, report with IDs). It matches the level-5 anchor exactly and is above level 4, where the 'when' would be less explicit.

Trigger Term Quality

Natural trigger phrases like "checking whether a branch is adequately tested", "test files", "untested exports", "error paths" and "routes" match what a user would actually say. It falls short of the level-5 anchor because common synonyms and variations such as "test coverage", "run the tests", or "CI" are absent.

Distinctiveness Conflict Risk

Terms like "branch", "adequately tested" and the T-M/U/E/R/S ID scheme carve a distinct niche. It is not level 5 because the skill shares the "review/check this branch" trigger space with general code-review and PR-review skills, creating minor overlap risk with closely related skills.