Conciseness

The body is dense and free of basic-concept padding, but "Adapting Existing Components for Fixtures" and "Writing Fixture-Friendly Components" duplicate the same guidance nearly verbatim — CSS decoupling from ancestor selectors, constructor DI over globals, shouldAutoFocus options, and exposing a public domNode each appear twice across ~100 redundant lines. This is more than the "minor instances" of the 4 anchor, so the content could be meaningfully tightened by merging those sections.

Actionability

Guidance is highly concrete: exact directory paths, the discovery glob ("src/**/*.fixture.ts"), a near copy-paste-ready basic pattern, a utilities table, named MCP tools, and worked mock/register code. Not a 5 because one instruction is unintelligible ("If you cannot see these tools, inform the user to them on" — a garbled sentence the reader cannot act on) and several examples require component-specific placeholders without an explicit note justifying that flexibility.

Workflow Clarity

"Running Fixtures Locally" gives a clear 3-step sequence (start server → list fixtures → screenshot), but the verification checkpoint is implicit: the skill never instructs the reader to inspect the captured screenshot (e.g., for blank or flickered renders) and iterate — a notable gap for a skill whose whole purpose is screenshot correctness. The authoring workflow (create file → render → screenshot → verify) is likewise scattered across sections rather than sequenced, matching the "checkpoints missing or implicit" anchor.

Progressive Disclosure

This is a single ~360-line SKILL.md with no bundle files (no references/, scripts/, or assets/ exist). Sections are well-organized with headers, but substantial self-contained material — the fixture-friendly component design guidance, the pre-registered service list, and the mocking patterns — is inlined where a one-level-deep reference file would keep SKILL.md an overview, matching the "content that should be separate is inline" anchor rather than the well-split 4 anchor.

Specificity

The description names concrete actions ("creating or updating component fixtures for screenshot testing", "designing UI components to be fixture-friendly") and a specific topic list ("fixture file structure, theming, service setup, CSS scoping, async rendering, and common pitfalls"). It falls short of a 5 because it lists fewer distinct concrete actions than the top anchor and omits activities the body actually covers, such as running/screenshotting fixtures and mocking services.

Completeness

Both what and when are explicit: the "when" is a concrete "Use when creating or updating component fixtures for screenshot testing, or when designing UI components to be fixture-friendly" clause with two distinct trigger conditions, and the "what" is an explicit coverage statement ("Covers fixture file structure, theming, service setup, CSS scoping, async rendering, and common pitfalls"). This matches the top anchor rather than 4, where the "when" would only be adequate rather than fully explicit.

Trigger Term Quality

Natural trigger phrases like "component fixtures", "screenshot testing", "UI components", and "fixture-friendly" match what a user in this codebase would actually say. Not a 5 because common synonyms and file-level triggers are missing — e.g., "visual testing", "screenshot tests", or the ".fixture.ts" file extension that would catch a user pointing at an existing fixture file.

Distinctiveness Conflict Risk

"Component fixtures for screenshot testing" is a clear niche with distinct triggers, unlikely to fire on unrelated skills. Held at 4 rather than 5 because the secondary trigger "designing UI components to be fixture-friendly" is broad enough that general UI component design requests could pull this skill in — a minor overlap risk with closely related design/testing skills.