Conciseness

The body is dense, fluff-free project-specific rules ('One grid tile is `1 x 1` world unit', 'Never mutate shared `M.*` material colors for one instance') with no explanations of concepts Claude already knows, fitting the 'efficient; minor instances that could be trimmed' anchor. It is not 5 because the ~100-line 'Material and palette rules' section interleaves many distinct topics (terrain maps, strata shaders, ore variants, fence styles, blast shields) that could be tightened or split; not 3 because nothing reads as padding or over-explanation.

Actionability

Guidance is fully concrete and executable: real file paths ('engine/world/53-voxel-avatar.js'), function names ('makeVoxelLiftEngine', 'voxelAppearanceMaterial()', 'twSetTextureSRGB(texture)'), specific API calls, and a copy-paste validation command ('perl -0ne ... | node --check'). Per the rubric's instruction-only note, this actionable specificity merits the top anchor despite few code blocks.

Workflow Clarity

Model import has a clear numbered sequence (compute Box3, center, scale, set shadows, tag userData, dispose) and a concrete validation checklist section ('Inline script passes...', 'Default camera shows the asset at the intended scale'), matching 'clear sequence with most checkpoints present'. It is not 5 because most other sections are unordered rule lists with no explicit error-recovery or fix-and-retry loops.

Progressive Disclosure

Clear section headers throughout, well-signaled one-level-deep cross-skill references at the top ('.codex/skills/tinyworld-single-file/SKILL.md', '.agents/skills/poly-pizza-api/SKILL.md'), and no buried or nested references, fitting the 'good structure; minor organization gaps' anchor. It is not 5 because niche sections (voxel avatar descriptors, cow/sheep animation) are inlined in a ~200-line file where a reference file could offload them.

Specificity

The description lists several concrete actions ('adding, importing, designing, reviewing, or animating') and enumerates specific topics ('Three.js procedural meshes, GLB/GLTF assets, Poly Pizza models, material palettes'), matching the 'several specific actions; minor gaps' anchor. It falls short of 5 because 'adding' and 'designing' are generic verbs and the heavily voxel-focused work from the body is absent.

Completeness

The 'when' is explicit and concrete ('Use when adding, importing, designing, reviewing, or animating...'), and the verb phrases imply the 'what', matching the 'both present; one could be more explicit' anchor. It is not 5 because the description never separately states what the skill provides (art-direction, scale, material, and import rules); not 3 because the enumerated activities do convey the skill's scope.

Trigger Term Quality

Natural domain terms like 'low-poly', 'stylized 3D', 'GLB/GLTF', 'Poly Pizza', and 'Tiny World builder' give good keyword coverage, fitting the 'good coverage; a few natural terms missing' anchor. It is not 5 because 'voxel' — used pervasively in the body and plausibly said by users — plus casual variants ('low poly', '.glb') are missing.

Distinctiveness Conflict Risk

'in Tiny World builder' combined with Poly Pizza/GLB/Three.js terminology carves a clear niche with distinct triggers and minimal conflict risk against generic 3D or document skills, matching the top anchor.