The body is generally lean and well-sectioned, but the opening rationale ('Without alt text, screen readers may read the file name of the image...') and the 'Ensures the button's purpose is clear to assistive technology' bullet explain a basic accessibility concept Claude already knows, so it could be tightened.

Gives concrete, specific guidance — 'Add an alt attribute to <input type="image">' with example values ('Search', 'Submit') and a precise check ('Verify that all <input type="image"> elements have a non-empty alt attribute'); for an instruction-only rule this is directly actionable, so the absence of a code block is not penalized per the rubric notes.

A simple single-task skill under 50 lines, clearly organized as Check → Fix → Explain → Code Review with an explicit 'Verify' check and a 'note how to verify the fix with browser accessibility tooling' step; the simple-skills note allows a 3, and this is not a destructive/batch op so no validation cap applies.

The body is a concise overview that delegates 'full implementation details, code examples, and framework-specific guidance' to references/rule.md — a clearly signaled, one-level-deep reference that exists as a real file — matching the score-3 anchor.

Lists multiple concrete actions — 'Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output' — matching the score-3 anchor; no explicit first/second-person pronouns, and the 'Use when...' phrasing mirrors the rubric's good examples, so no voice penalty applies.

Explicitly answers both: 'Use when reviewing rendered HTML ... related to Provide alt text for image buttons' (when) and 'Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output' (what), matching the score-3 anchor with an explicit 'Use when' trigger.

'Provide alt text for image buttons' is a natural term, but the trigger is framed as 'reviewing rendered HTML, interactive components, or design-system patterns' — broad, meta-review phrasing rather than the variations a user would naturally say, so common variations are only partly covered.

The rule itself ('alt text for image buttons') is a clear niche, but the shared 'reviewing rendered HTML, interactive components, or design-system patterns' trigger framing could plausibly fire for sibling frontendchecklist accessibility skills, so overlap risk remains.