Conciseness

Every line is a specific instruction — layer specs, stroke widths ("0.5–1px"), rotation periods ("60s, 90s, 180s"), keyframe names, and a copy-paste output contract. There is no padding, no explanation of concepts Claude already knows (no 'what is CSS animation' filler), and no time-sensitive version information. This matches the lean-and-efficient anchor exactly.

Actionability

Guidance is highly concrete and executable for an instruction-only skill: named layers with dimensions ("~28% of the canvas wide"), named @keyframes to implement, `data-od-id` attributes to include, and a copy-paste artifact wrapper. It falls just short of the fully-executable anchor because no HTML/CSS skeleton or example snippet is provided — Claude must synthesize the structure from prose, and 'subtle dotted grid texture ... at 22–32px intervals' leaves some parameters to judgment.

Workflow Clarity

The 5-step workflow (Read DESIGN.md → Compose → Animate → Write → Self-check) is clearly sequenced and ends with an explicit validation step containing three concrete checks ("still reads as a poster with motion paused at frame 0", "at least 3 layers move at different speeds", "accent appears once"). This matches the anchor for a clear sequence with explicit validation; the operation is not destructive/batch so no cap applies.

Progressive Disclosure

The skill has no bundle files and needs none: the body is short (~56 lines), single-purpose, and cleanly split into Workflow and Output contract sections with nothing that belongs in a separate file. Per the rubric's simple-skill guidance, a short, well-organized skill with no external references scores 5.

Specificity

The description lists several concrete components ("rotating type ring, animated globe, ticking timer, parallax labels") and a concrete deliverable ("Renders as a hero video poster"), which would anchor at 4 — but it slips into second person ("you can hand straight to HyperFrames"), and the guidelines require reducing specificity by 1 for second-person voice. Re-checked against anchors: above 2 (domain plus multiple concrete elements, not minimal), penalized below 4.

Completeness

What is answered concretely ("A single-frame motion-design composition with looping CSS animations...") and when is explicit with concrete trigger phrases ("Use when the brief asks for 'motion design', 'animated hero', 'loop', 'video poster', 'title card'..."). This matches the anchor for clearly and explicitly answering both.

Trigger Term Quality

Natural trigger phrases are explicitly quoted ("motion design", "animated hero", "loop", "video poster", "title card") plus the tool name HyperFrames — good coverage users would actually say. A few common synonyms (e.g. "motion graphic", "kinetic typography", "animated logo") appear only in the frontmatter triggers list, not the description itself, so it falls just short of the comprehensive-synonyms anchor.

Distinctiveness Conflict Risk

The HyperFrames/keyframe-exporter niche and motion-design trigger set make it mostly distinct from generic web-design or branding skills. The bare trigger word "loop" is generic enough to risk firing on unrelated requests (e.g. iterating in code), keeping it just below the minimal-conflict anchor.