Conciseness

The body is lean and directive with no explanation of concepts Claude already knows — every section gives constraints rather than background. Minor redundancy keeps it from a 5: the "Protect the proven qualities" checklist restates constraints already given (inner radius readability, wall softness/spokes, enemy range fairness), so it fits 'efficient; minor instances... that could be trimmed' better than 'every token earns its place'.

Actionability

Guidance is highly concrete and specific ("Combine radial and obstacle fog with `max`, then cap final opacity"; "linear filtering, horizontal repeat wrapping, no mipmaps"; "Disable depth test, depth write, and tone mapping"), which per the rubric's instruction-skill note is not penalized for lacking code. However, no executable commands are given — validation is described categorically ("project lint and build", "pure perception and opacity tests") without the actual commands — placing it at 'mostly executable guidance; concrete... with minor gaps' rather than the copy-paste-ready score-5 anchor.

Workflow Clarity

The workflow is clearly dependency-ordered (perception truth → lookup → overlay → gameplay → lifecycle), preceded by an "Inspect before editing" phase, followed by an ordered tuning procedure with iterative feedback ("Add angular smoothing until spokes disappear") and an explicit validation gate ("Read validation.md before claiming completion"). It falls short of the score-5 anchor because validation lacks an explicit error-recovery loop — no 'if a test fails, fix and re-run' step — leaving it at 'clear sequence with most checkpoints present; minor validation gaps'.

Progressive Disclosure

The body is a well-organized overview with clearly signaled, one-level-deep references — "Read [mechanics.md](references/mechanics.md) before implementing" and "Read [validation.md](references/validation.md) before claiming completion" — and both referenced files exist in the bundle (14KB and 8KB of detail respectively) with no nested references inside them. Detail is appropriately split out while the body stays overview-level, matching the score-5 anchor.

Specificity

The description lists multiple concrete actions ("Implement, tune, debug, or validate") plus a comprehensive inventory of specific capabilities — visibility masks, obstacle-aware line of sight, vision ranges, targeting rules, shader artifacts, ray budgets, lifecycle integration, and deterministic tests. This matches the 'multiple specific concrete actions; comprehensive coverage' anchor, not the score-4 anchor which expects minor coverage gaps.

Completeness

It explicitly answers both: what it does ("Implement, tune, debug, or validate soft wall-aware fog of war and gameplay perception in Three.js action games") and when to use it via a concrete "Use for..." clause enumerating specific trigger scenarios. This matches the score-5 anchor exactly; the score-4 anchor applies when the 'when' is less explicit, which is not the case here.

Trigger Term Quality

Strong natural terms users would actually say: "fog of war", "line of sight", "vision ranges", "targeting", "spokes or seams", "ray budgets", "Three.js". A few common synonyms and variations are missing (e.g., "field of view", "LOS", "visibility/fog shader" phrasing beyond the artifact list), so it fits the 'good keyword coverage; a few natural terms missing' anchor rather than the comprehensive score-5 anchor.

Distinctiveness Conflict Risk

Clear niche — fog of war and gameplay perception in Three.js action games — with distinct triggers (visibility masks, fog shader spokes, hidden-enemy targeting, deterministic fog tests) that would rarely collide with other skills. It matches the 'clear niche with distinct triggers; minimal conflict risk' anchor.