Conciseness

Mostly efficient but includes unnecessary explanation: the opening statistics ('Approximately 15% of adults have some degree of hearing loss... legal compliance failure under the ADA, EN 301 549') is motivational padding, and the captions-vs-subtitles distinction is explained twice ('Subtitles and captions are different...' in Quick Reference and again in the Explain section), repeating a concept Claude already knows. Matches anchor 3 ('mostly efficient but includes some unnecessary explanation or could be tightened'). Not 2: the padding is limited and the Check/Fix sections are lean and task-focused; not 4: the duplicated conceptual explanation is a clear instance of over-explanation.

Actionability

Concrete, attribute-level guidance: 'Add `<track kind='captions' srclang='en' label='English' src='captions-en.vtt' default>`', 'include... descriptions of relevant sounds (e.g., `'[applause]'`, `'[upbeat music]'`)', and specific check criteria ('not empty, not just music notes'). Matches anchor 4 ('mostly executable guidance; concrete code or commands with minor gaps'). Not 5: no complete `<video>` markup example and no sample .vtt cue syntax with timestamps, so it is not fully copy-paste ready; not 3: the guidance is executable and specific, not high-level hints.

Workflow Clarity

Clear Check → Fix → Explain → Code Review sequence with explicit checkpoints: 'check that the `.vtt` file exists and is valid (not empty, not just music notes)' and 'note how to verify the fix with browser accessibility tooling or assistive tech'. Matches anchor 4 ('clear sequence with most checkpoints present; minor validation gaps'). Not 5: no explicit fix-then-re-check feedback loop is articulated; not 3: validation checkpoints are present and explicit, not missing or implicit.

Progressive Disclosure

The body is a clear overview with well-organized sections (Quick Reference, Check, Fix, Explain, Code Review) and a single, clearly signaled one-level reference: 'see `references/rule.md`', which exists as a real 94-line file with only external links (no nested .md references). Matches anchor 5 ('clear overview with well-signaled one-level-deep references; content appropriately split; easy navigation'). Not 4: there are no organization gaps — the split between overview and detail reference is clean.

Specificity

Quotes several concrete actions: 'Prerecorded videos require `.vtt` caption files via `<track>`', 'check that the video platform captions are enabled', 'Audio-only content requires transcripts instead', 'Video-only content (no audio) requires a text alternative'. This matches the 'lists several specific actions; minor gaps' anchor. Not 5: coverage is framed as requirements/checks rather than a comprehensive set of actions the skill performs; not 3: it goes well beyond 1-2 actions.

Completeness

Both parts are present: what ('Prerecorded videos require `.vtt` caption files via `<track>`... check that the video platform captions are enabled') and when ('Use when applies to all `<video>` elements and third-party video embeds'). Matches anchor 4 ('both what and when; when could be more explicit or specific') because the trigger clause is awkwardly phrased ('Use when applies to all') and less natural than the anchor-5 example. Not 3: 'when' is explicitly stated, not weakly implied; not 5: the garbled trigger phrasing keeps it below the clean 'concrete trigger phrases' anchor.

Trigger Term Quality

Natural keywords present: 'captions', 'video', 'YouTube', 'Vimeo', '`.vtt`', 'transcripts', '`<track>`'. This fits 'good keyword coverage; a few natural terms missing' — e.g., 'subtitles', 'WebVTT', 'track kind', and 'accessibility' are absent. Not 5: not comprehensive with synonyms; not 3: coverage is well beyond 'some relevant keywords'.

Distinctiveness Conflict Risk

Clear niche — video captions on `<video>` elements and YouTube/Vimeo embeds — with distinct triggers ('`.vtt`', '`<track>`', 'captions', 'YouTube', 'Vimeo') that would not fire for other accessibility or media skills. Matches anchor 5 ('clear niche with distinct triggers; minimal conflict risk'). Not 4: the overlap risk with, say, a general media skill is minimal given the explicit scope boundaries (audio-only → transcripts, video-only → text alternative).