Conciseness

The ~30-line body is lean with no concept explanations Claude already knows — the Quick Reference bullets carry real information ('Use onerror to replace broken images with fallbacks', 'Consider skeleton loaders', 'Log image errors'). It falls short of anchor 5 because of minor trimmable padding: the intro sentence duplicates the reference file's 'Why It Matters' verbatim, and the 'Explain how proper error handling for images improves user experience' section adds no actionable content.

Actionability

The Quick Reference names concrete techniques (onerror, skeleton loaders, error logging) but the Check and Fix sections are vague direction — 'Check if the website handles broken images gracefully' and 'Implement fallback images or placeholder content' — with no code or specifics in the body. This matches anchor 3 ('some concrete guidance but incomplete; missing key details'), such as the critical onerror=null infinite-loop guard that only appears in the reference file.

Workflow Clarity

The Check → Fix → Explain → Code Review sections imply a sequence and the Code Review section gestures at verification ('describe how to confirm the fix in DevTools'), but no explicit checkpoints are given in the body and the concrete verification steps (DevTools request blocking, invalid URLs) live only in references/rule.md. This fits anchor 3 ('sequence present but checkpoints missing or implicit') rather than anchor 4.

Progressive Disclosure

The body is a concise, well-sectioned overview that defers all implementation details to a single clearly signaled, one-level-deep reference — 'For full implementation details, code examples, and framework-specific guidance, see references/rule.md' — and that file exists and contains exactly those details (HTML/React/Next.js examples, verification steps). This matches anchor 5 exactly; no inline content belongs in a separate file and navigation is trivial.

Specificity

The description lists several concrete actions — 'Check encoded size, rendered size, loading strategy, and above-the-fold impact together' and 'reviewing image assets, markup, and CDN or build transforms' — matching the 'several specific actions' anchor. It stays at 4 rather than 5 because the actions mischaracterize this skill: nothing describes the actual error-handling work (fallbacks, onerror, placeholders), so coverage is not comprehensive.

Completeness

An explicit 'Use when...' trigger clause is present, but the 'what' is wrong: 'Check encoded size, rendered size, loading strategy, and above-the-fold impact' describes a different rule (image optimization/sizing), not this skill's graceful error handling. Because the stated capability misaligns with the skill body, the effective 'what' is missing, which matches anchor 3 better than anchor 4.

Trigger Term Quality

It includes some relevant keywords ('image assets', 'markup', 'image loading errors', 'CDN or build transforms') but misses the natural phrases a user would actually say, such as 'broken images', 'image fallback', or 'placeholder'. This fits anchor 3 ('some relevant keywords but missing common variations or synonyms') and not anchor 4, which requires good coverage with only a few natural terms missing.

Distinctiveness Conflict Risk

The phrase 'related to Handle image loading errors gracefully' gives it a niche, but the dominant trigger surface ('encoded size', 'loading strategy', 'above-the-fold impact', 'CDN or build transforms') overlaps heavily with sibling image-optimization and lazy-loading skills, so it could trigger for the wrong skill. This is 'somewhat specific but could still overlap with similar skills' (anchor 3), not anchor 4's 'minor overlap risk'.