Conciseness

The body is dense and assumes competence — no library tutorials, no 'what is parallax' padding — and every section carries novel guidance (routing table, browser contract, technique chooser). It falls short of 5 because of run-on compound-noun enumerations like 'visual-density role, interactive discovery affordance, asset-continuity requirement, scroll-controlled media behavior' in step 5, which could be trimmed or pushed to a reference without losing meaning.

Actionability

Concrete, executable decision rules dominate: 'native scroll and position: sticky for pinning / IntersectionObserver or Scrollama for step triggers / Motion or GSAP ScrollTrigger for complex React choreography', plus a precise routing table and verified reference files. Not a 5: the core artifact — the scene contract — is never shown; a minimal example scene object (trigger range, visual state, fallback) would make step 5 copy-paste ready instead of leaving the reader to infer the schema.

Workflow Clarity

The 11-step Working Pattern is clearly sequenced with validation checkpoints — step 7 ('If the scene only adds drama, simplify or add real evidence') is an explicit fix loop, and step 11 plus the acceptance criteria in Output Expectations act as test checklists. Not a 5: the error-recovery path is one-line rather than a validate-fix-retry loop, and steps 2-6's branching (fictional / art-directed / embedded layers) interleaves conditions inside a flat sequence.

Progressive Disclosure

Good structure overall: ~100-line overview with technique selection, routing, and expectations kept in SKILL.md while detail lives in three real, clearly listed one-level-deep bundle files (all verified present in ./references/). Not a 5: the References section is a bare path list with no per-file description ('**Scene contracts**: See ...' style is the top anchor), and 3 of 6 referenced paths (`../../references/foundations/*`) point outside the bundle where their existence cannot be signaled or verified by a reader of this skill alone.

Specificity

The description names the domain ('parallax scrolling and scrollytelling data visualizations') with exactly two concrete actions — 'Design and implement' — matching the anchor 'Names domain and 1-2 concrete actions, but not comprehensive'. It is not a 4 because 'several specific actions' (e.g., storyboard scenes, build scroll-scrubbed charts, pin sticky graphics) are not enumerated, only implied through the trigger list.

Completeness

It explicitly answers both questions with concrete trigger phrases: 'what' is 'Design and implement parallax scrolling and scrollytelling data visualizations' and 'when' is 'Use when the user asks for... [12 concrete triggers]'. This matches the anchor 'Clearly and explicitly answers both what AND when with concrete trigger phrases'.

Trigger Term Quality

Trigger coverage is comprehensive and natural: 'parallax scrolling, scrollytelling, scroll-driven timelines, sticky graphics, Scrollama, ScrollTrigger, ScrollTimeline, view timelines, rich-media timelines, moviescrollers, scroll-scrubbed charts, staged narrative reveals' — covering synonyms, library names, and API names a user would actually say. No common variation is missing.

Distinctiveness Conflict Risk

Scroll-driven narrative visualization is a clear niche, and every trigger term is scroll-specific ('scroll-scrubbed', 'sticky graphics', 'Scrollama'), minimizing conflict with general charting or animation skills. Not a 4: even the broadest trigger ('interactive visual stories') is immediately qualified by 'where scrolling changes a data visualization or media scene'.