Conciseness

The body is short (~30 lines) but includes content Claude already knows: the Quick Reference bullets ("Custom properties cascade and inherit — they can be overridden at any scope", "Use var(--name, fallback) to provide fallback values") are CSS basics, and the opening paragraph duplicates the "Why It Matters" text in references/rule.md verbatim. This is more than 'minor instances of over-explanation' (score 4), but the padding is limited, so it sits at 'mostly efficient but includes some unnecessary explanation'.

Actionability

The Check and Fix sections give concrete, specific instruction: "Find hard-coded color values, spacing values, and font sizes" and "Extract repeated and meaningful values into CSS custom properties on :root and replace all usages with var() references" — actionable without inline code, which per the scoring notes is acceptable for an instruction-only skill. It falls short of score 5 because criteria like what counts as a 'meaningful' value and fallback usage are left implicit, and the executable code examples only live in the reference file.

Workflow Clarity

The Check → Fix → Explain → Code Review sections imply a sequence, but it is never made explicit, there is no ordering guidance among the four modes, and validation checkpoints are absent (the description's "check the rendered layout across breakpoints... before proposing a fix" step is not operationalized in the body). This matches 'sequence present but checkpoints missing or implicit' rather than the simple-skill exception at 5, since the skill presents four parallel modes rather than one unambiguous action.

Progressive Disclosure

The body is a concise overview that clearly signals a single one-level-deep reference: "For full implementation details, code examples, and framework-specific guidance, see `references/rule.md`" — and references/rule.md exists and contains those details without further nested references. Content is appropriately split between the short overview and the detailed rule file, matching the clear-overview anchor.

Specificity

The description names the domain ("stylesheets, component styles, and responsive behavior") and a couple of concrete actions ("Check the rendered layout across breakpoints and interaction states before proposing a fix"), but the core capability is obscured by embedding the raw rule title ("related to Use CSS custom properties for design tokens") mid-sentence, so coverage of what the skill actually does is not comprehensive. It fits the 'names domain and 1-2 concrete actions' anchor better than score 4's 'several specific actions', since the token-extraction capability itself is never stated as an action.

Completeness

An explicit 'when' is present ("Use when reviewing stylesheets, component styles, and responsive behavior related to...") and a partial 'what' exists ("Check the rendered layout across breakpoints and interaction states before proposing a fix"), so it clears the score-3 cap concern. It is not score 5 because the primary 'what' — extracting hard-coded values into custom properties — is only conveyed through the awkwardly embedded rule title rather than a clear capability statement.

Trigger Term Quality

Good natural keyword coverage: "reviewing stylesheets", "component styles", "responsive behavior", "CSS custom properties", "design tokens", "breakpoints", "interaction states" are phrases users would naturally say. It falls short of score 5 because the most common synonym "CSS variables" and file extensions like ".css" are missing, and it is not merely 'some relevant keywords' (score 3).

Distinctiveness Conflict Risk

The niche is fairly distinct — "CSS custom properties", "design tokens", and "breakpoints" are specific triggers that would not fire for unrelated skills. Minor overlap risk remains with general CSS/layout review or theming skills, matching 'mostly distinct; minor overlap risk with closely related skills' rather than the clear-niche anchor at 5.