Conciseness

The body is short (~30 lines) and mostly lean, with each section earning its place (Quick Reference rules, Check patterns, Fix direction). It is a 4 rather than 5 because of minor over-explanation that could be trimmed: the intro sentence and the 'Explain' section re-teach why screen-reader redundancy is bad — knowledge Claude already has — and the 'Code Review' paragraph largely restates the description boilerplate.

Actionability

The Check section gives concrete scan patterns ("redundant phrases like 'image of', 'photo of', or text that duplicates surrounding content") and the Fix section states the remedy, but the body contains no example markup, selector, command, or before/after alt-text pair — those concrete artifacts live only in references/rule.md. This matches 'some concrete guidance but incomplete; missing key details' rather than 4, which requires mostly executable guidance in the body itself.

Workflow Clarity

For this simple single-purpose skill the sequence is clear and unambiguous: Quick Reference → Check → Fix → Explain, with verification steps available in the reference file. It does not reach 5 because the body itself includes no verification checkpoint (verification is deferred entirely to references/rule.md) and the 'Code Review' section overlaps with 'Check', creating mild redundancy rather than a crisp single flow.

Progressive Disclosure

The body is a concise overview with a clearly signaled, one-level-deep pointer — "For full implementation details, code examples, and framework-specific guidance, see `references/rule.md`" — and that file exists and delivers exactly what is promised (incorrect/correct code examples, best practices, verification) without further nesting. This matches the 'clear overview with well-signaled one-level-deep references; easy navigation' anchor.

Specificity

Quotes like "Check native semantics first, then inspect keyboard behavior, focus flow, accessible names, and screen-reader output" list several concrete inspection actions, matching the 'several specific actions; minor gaps in coverage' anchor. It is not a 5 because the core capability of the rule — identifying and fixing redundant alt text — is never stated as an action, and it is not a 3 because more than 1-2 concrete actions are explicitly named.

Completeness

Both halves are explicit: 'when' via "Use when reviewing rendered HTML, interactive components, or design-system patterns related to Avoid redundant image alternative text" and 'what' via the listed check/inspect actions. It falls short of the 5 anchor because the 'what' describes generic accessibility inspection rather than concretely stating what the skill does about redundant alt text, leaving the primary action implied by the rule name.

Trigger Term Quality

Relevant keywords are present ("reviewing rendered HTML, interactive components", "screen-reader", "image alternative text") but the natural phrase users would actually say — "alt text" or "alt attribute" — never appears, and no synonyms/extensions are covered. This fits 'some relevant keywords but missing common variations or synonyms' rather than 4, where only a few natural terms would be missing — here the single most important trigger term is absent.

Distinctiveness Conflict Risk

The rule topic is specific, but the broad trigger clause "reviewing rendered HTML, interactive components, or design-system patterns" is generic accessibility-review boilerplate that would fire equally for any sibling a11y rule skill, so overlap with closely related skills is real. It is not 4 because the only distinguishing content is the embedded rule name, and not 2 because the alt-text topic does provide some narrowing.