Conciseness

The body assumes Claude's competence (no explanation of what CI, Vitest, or E2E testing is) and every rule carries a repo-specific payoff, but time-sensitive facts — "on 2026-09-29 the Fast tests gate waited a median 445 s", "moved to Enterprise Cloud in October 2026, which raises the pool to 500 jobs" — sit in the motivation section rather than a deprecated/old-patterns section and will rot. Efficient with minor trimmable material fits 4; not 3 (no genuinely unnecessary explanation) and not 5 (the dated capacity history costs tokens without guiding action).

Actionability

Guidance is concrete and executable throughout: a copy-paste test command ("node --experimental-strip-types --test scripts/ci-change-scope.test.ts ..."), named scripts and outputs (ci-change-scope.ts, query_budget_apps, script_tests, MIN_SHARD_FILES), exact APIs (testInfo.outputPath, expectOnlyChanged, app.savedNodes), and tooling (actionlint). Specific examples cover the common cases, matching the 5 anchor rather than 4's "minor gaps".

Workflow Clarity

"Proving a CI change" is an explicit validation loop — add classifier test cases, run the test command, verify against real main history and post before/after, run each run: snippet against matching and empty inputs, actionlint, and mind the self-test gap — and "Adding a test" is sequenced from should-it-exist to where-it-lives to what-runs-it. Clear sequences with explicit checkpoints fit the 5 anchor; nothing lands in the destructive/batch cap.

Progressive Disclosure

The bundle is one clearly signaled, one-level-deep reference ("Design's harness ... and its traps are in references/design-e2e.md") that exists and correctly absorbs the harness API table and trap list, while the body keeps the decision-level guidance with well-organized sections. Content is appropriately split with easy navigation, matching the 5 anchor; 4's "minor organization gaps" does not apply.

Specificity

The description lists three concrete capabilities — "Where a new test belongs", "how to write a browser E2E test that fails when the feature breaks", and "how to scope CI jobs, steps, and workflow triggers" — comprehensively covering the skill's scope with no gaps, matching the 5 anchor rather than 4's "minor gaps in coverage".

Completeness

It explicitly answers both questions: the first sentence states what the skill does, and "Use when adding, moving, or writing a test... or when a job is slow or runs on unrelated changes" gives concrete when-triggers. Clearly the 5 anchor, not 4 where the 'when' is only adequate.

Trigger Term Quality

Triggers span synonyms and natural phrasing: "adding, moving, or writing a test", "Design E2E specs", "CI job, step, or workflow", and complaint-shaped triggers like "when a job is slow or runs on unrelated changes". Coverage is comprehensive, fitting the 5 anchor over 4's "a few natural terms missing".

Distinctiveness Conflict Risk

The combined test-placement and CI-scoping niche is mostly distinct, but triggers like "adding... a test" could overlap with closely related sibling skills the body itself cites (test-audit, design-editor-architecture), so 4's "minor overlap risk with closely related skills" fits better than 5's "minimal conflict risk".