Conciseness

The body is short and doesn't explain basics Claude already knows, but the 'Quick Reference' bullets duplicate the intro ('Using unsupported attributes can confuse assistive technologies' restates 'Invalid ARIA attributes are ignored by screen readers or may cause them to misinterpret') and 'Ensures the accessibility tree remains valid and meaningful' is filler. Not 4 because real redundancy exists that could be trimmed; not 2 because there is no padded multi-paragraph over-explanation.

Actionability

The body states goals rather than executable steps: 'Verify that all ARIA attributes used on elements are valid for their assigned WAI-ARIA roles' and 'Remove or correct ARIA attributes that are not supported' give no method — no role/attribute pairing examples, no checker commands, no spec lookup guidance; the concrete material (code example, axe/Lighthouse verification) lives only in references/rule.md. Not 3 because even the body's core Check/Fix sections lack any concrete detail; not 1 because the sections do name the exact rule target and the reference pointer is explicit.

Workflow Clarity

Check → Fix → Explain → Code Review provides a recognizable sequence, but validation checkpoints are only implicit ('note how to verify the fix with browser accessibility tooling') and the actual verification steps are delegated to the reference. Not 4 because no explicit verify-then-proceed checkpoint exists in the body; not 2 because the section ordering does define a coherent rough sequence for the review task.

Progressive Disclosure

The body is a lean overview with well-organized sections and exactly one clearly signaled, one-level-deep reference ('For full implementation details, code examples, and framework-specific guidance, see references/rule.md'), which exists and appropriately holds the code example, exceptions, standards, and verification detail. Not 4 because there are no organization gaps: the split is clean and navigation is trivial.

Specificity

Lists several concrete actions ('Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output') with only minor gaps. Not 5 because no flag/fix/reporting actions are named and the 'when' clause awkwardly embeds the rule title instead of crisp capabilities; not 3 because multiple specific inspection actions are explicitly stated rather than just 1-2.

Completeness

Explicitly answers both 'what' ('Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output') and 'when' ('Use when reviewing rendered HTML, interactive components, or design-system patterns'). Not 5 because the when-clause is convoluted ('related to Use only allowed ARIA attributes for each role') and less explicit than concrete trigger phrases; not 3 because a real 'Use when...' clause is present.

Trigger Term Quality

Good natural keyword coverage ('rendered HTML', 'interactive components', 'design-system patterns', 'keyboard behavior', 'focus flow', 'accessible names', 'screen-reader output', 'ARIA attributes'). Not 5 because common variations users actually say like 'accessibility', 'a11y', 'WAI-ARIA', or 'aria-*' are missing; not 3 because coverage goes well beyond a couple of generic terms.

Distinctiveness Conflict Risk

The trigger template ('Use when reviewing rendered HTML, interactive components, or design-system patterns related to...') would be identical across sibling frontend-checklist accessibility skills, with only the embedded rule title ('Use only allowed ARIA attributes for each role') distinguishing it. Not 4 because overlap risk with closely related ARIA/accessibility skills is real, not minor; not 2 because the rule title and ARIA-specific vocabulary do carve out a recognizable niche.