Conciseness

The body is short and mostly lean, but "Without alt text, screen readers may read the file name of the image, leaving users unable to determine the function of the button" explains a concept Claude already knows, and the Quick Reference bullets ("Add an `alt` attribute to `<input type='image'>`") duplicate the Check/Fix sections. Not 5: these minor instances could be trimmed; not 3: the padding is limited to a couple of spots.

Actionability

"Verify that all <input type='image'> elements have a non-empty 'alt' attribute" and "Add an 'alt' attribute ... that describes the action ... (e.g., 'Search', 'Submit')" are concrete, executable guidance with a specific selector and example values. Not 5: no inline good/bad markup example is shown (deferred to references/rule.md); not 3: the guidance is specific and directly actionable, not pseudocode.

Workflow Clarity

This is a simple single-purpose skill under 50 lines whose action is unambiguous: Check (specific selector and non-empty alt condition) then Fix (add descriptive alt with examples), followed by Explain and Code Review framing. No destructive or batch operations, so no validation cap applies; the simple-skill exception holds.

Progressive Disclosure

The body is a well-organized overview with a clearly signaled, one-level-deep reference ("For full implementation details, code examples, and framework-specific guidance, see `references/rule.md`"), and that file exists in the bundle. Matches the anchor for clear overview with well-signaled one-level-deep references.

Specificity

"Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output" lists several concrete review actions. Not 5: the actions are generic review boilerplate not tailored to this rule, and "where relevant" hedges coverage; not 3: well more than 1-2 concrete actions are named.

Completeness

Both parts are present: an explicit trigger ("Use when reviewing rendered HTML, interactive components, or design-system patterns related to Provide alt text for image buttons") and a what ("Check native semantics first, then inspect..."). Not 5: the what is indirect — it never plainly states the core task (verify image buttons have descriptive alt text) — and the trigger is templated; not 3: the when clause is explicit, not merely implied.

Trigger Term Quality

Natural terms like "alt text", "image buttons", "accessible names", and "screen-reader" are present, giving good keyword coverage. Not 5: common variations such as "input type='image'", "a11y", or "image submit button" are missing; not 3: the core natural phrases users would say are included.

Distinctiveness Conflict Risk

"Provide alt text for image buttons" carves a clear niche with minimal conflict risk. Not 5: the trigger boilerplate ("reviewing rendered HTML, interactive components, or design-system patterns") would match sibling accessibility-rule skills identically, leaving minor overlap risk with closely related skills.