Conciseness

The body is dense and prescriptive throughout with no explanations of concepts Claude already knows — every section is skill-specific constraint (beat ledger fields, style bible, encoder flags). A few spots could be trimmed, e.g. "Use one codec and encode profile across every clip" overlaps the pinned ffmpeg command, and the House rules / Bar sections repeat constraints also implied by the verification checklist. This is 'efficient; minor instances of over-explanation that could be trimmed', not the lean anchor-5 where every token earns its place.

Actionability

There is a copy-paste ffmpeg encode command, a concrete JS story-config example, and precise numeric parameters (scroll weight 0.7–1.8 viewport heights, DPR cap of 2, widths 390/768/1024/1440, 6–15 second clips). However the actual runtime implementation (scroll conductor, chapter mapping, fallback wiring) is delegated to demo files via pointers like "Use [demo/video/index.html](demo/video/index.html)" — and those files are not in the bundle, so a large part of the executable guidance is unreachable. Mostly executable guidance with minor-to-material gaps, fitting anchor 4 rather than the fully copy-paste-ready anchor 5.

Workflow Clarity

The sequence is explicit and well-ordered: contract (goal/house rules/bar) → read source → story map → style bible → choose one mode → mode-specific build → shared page contract → verify → deliverables. Validation is explicit: a 10-point verification checklist covering story, timing, reverse scroll, performance, responsive, accessibility, integrity, console, and mode proof, followed by a genuine feedback loop — "Repeat: build, verify, close the largest gap. Stop when no material gap remains against the bar." This matches the top anchor of clear sequence with explicit validation steps, feedback loops, and a checklist for a complex process.

Progressive Disclosure

The in-body organization is good and references are clearly signaled one level deep, but the disclosure structure is fictional: the bundle contains no demo/ directory and no REFERENCES.md, so every referenced path — [demo/video/index.html](demo/video/index.html), [demo/threejs/PROMPT.md](demo/threejs/PROMPT.md), [demo/html-data/index.html](demo/html-data/index.html), [demo/index.html](demo/index.html), and [REFERENCES.md](REFERENCES.md) — is broken. Scoring against the actual bundle structure, navigation to the detailed material is impossible, which is a worse failure than anchor 3's 'references present but not clearly signaled'; the structure is present in name only.

Specificity

The description lists multiple concrete capabilities with comprehensive coverage of its domain: "Turn an article, case study, brand narrative, product journey, or long-form story into a cinematic scroll-driven landing page" enumerates the input types, the output artifact, and all three implementation modes ("scrubbed video, a real-time Three.js world, or semantic HTML/SVG data and typography"). This matches the anchor for multiple specific concrete actions with comprehensive coverage, not the anchor below it, which requires minor gaps in coverage.

Completeness

Both what and when are explicitly answered: the first sentence states what the skill does and how, and the "Use when the user asks for..." clause gives concrete trigger phrases. This mirrors the anchor example that clearly and explicitly answers both what AND when, and is clearly not the anchor-4 case where 'when' could be more explicit.

Trigger Term Quality

"Use when the user asks for a scroll world, fly-through landing page, article-to-website transformation, animated planet, data scrollytelling, video-scrubbed page, connected visual journey, or story-led alternative to ordinary stacked sections" covers natural synonyms and phrasings comprehensively, including informal ones ("scroll world") and a contrast phrasing ("story-led alternative to ordinary stacked sections"). This is comprehensive natural-term coverage including synonyms, matching the top anchor rather than the 'a few natural terms missing' anchor below.

Distinctiveness Conflict Risk

The niche (scroll-driven storytelling landing pages) and its triggers ("data scrollytelling", "video-scrubbed page") are distinct, but broader terms like "landing page" and "animated planet" have minor overlap risk with generic web-page and Three.js skills. This fits 'mostly distinct; minor overlap risk with closely related skills' better than the anchor-5 'minimal conflict risk', since a plain request to build a landing page could plausibly route here over a general web skill.