Conciseness

The body is short and free of concept over-explanation, but the fact "Screen readers announce 'list with X items'" is repeated three times (intro, Quick Reference bullet, Explain), and the Explain and Code Review sections partially restate each other. This fits 'Mostly efficient but includes some unnecessary explanation or could be tightened' — not level 4, which requires only minor trimming.

Actionability

The Fix section gives specific, executable guidance — "Wrap related items in appropriate list elements: ul for unordered lists, ol for numbered sequences, dl for definition pairs. Use li for list items and proper dt/dd" — and Quick Reference maps each element to its use case. Per the rubric's instruction-skill note, the absence of inline code is not penalized since the guidance is actionable; it stays at 4 rather than 5 because the concrete before/after markup examples live only in the referenced file.

Workflow Clarity

The Check → Fix → Explain → Code Review sequence is clearly ordered and unambiguous for a simple single-purpose skill, and the Code Review section supplies a verification hint ("note how to verify the fix with browser accessibility tooling"). It falls just short of 5 because the Check and Code Review sections overlap in purpose without an explicit distinction, leaving a minor clarity gap.

Progressive Disclosure

The body is a concise, well-sectioned overview and defers implementation details, code examples, and framework guidance to a single one-level-deep reference, clearly signaled at the end: "see `references/rule.md`" — the file exists in the bundle. This matches the anchor 'Clear overview with well-signaled one-level-deep references; content appropriately split'.

Specificity

The description lists several concrete inspection actions — "Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output" — which matches the anchor for several specific actions with minor gaps. It falls short of 5 because coverage is inspection-only (no fix/implementation actions) and the action list is generic accessibility boilerplate rather than comprehensive for the list-semantics niche.

Completeness

Both parts are present: an explicit "Use when reviewing rendered HTML, interactive components, or design-system patterns" trigger clause and a 'what' via the concrete inspection actions. It sits at the level-4 anchor because the 'when' could be more precise — the differentiating phrase "related to Use semantic list elements" is grammatically broken, weakening what would otherwise be a level-5 explicit trigger.

Trigger Term Quality

Relevant keywords are present ("rendered HTML", "interactive components", "design-system patterns", "semantic list elements", "screen-reader") but the phrase "related to Use semantic list elements" is awkward template stitching, and natural variations users would say — "ul", "ol", "dl", "list markup", "accessibility audit" — are missing. This fits the anchor 'Some relevant keywords but missing common variations or synonyms' better than the level-4 anchor, where a user would find most natural trigger terms present.

Distinctiveness Conflict Risk

The only differentiator from sibling accessibility skills is the phrase "Use semantic list elements"; the entire action list ("Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output") is generic template text that would equally trigger semantic-tables, landmarks, or heading-structure skills. This matches 'Somewhat specific but could still overlap with similar skills' rather than level 4, which requires only minor overlap risk.