Conciseness

The body is lean and bulleted, assumes competence (no explanations of what engines or renderers are), and mostly earns its tokens — e.g. "Save serializable simulation state, not renderer objects." It misses a 5 due to redundancy: the Engine Selection bullets duplicate the decision table deferred to engine-selection.md, and the "Do Not Stay Here When" bullets largely invert the "Use This Skill When" list.

Actionability

The rules are concrete and executable for an instruction-only skill — specific input action names (`move`, `confirm`, `cancel`, `ability-1`, `pause`), "standardize on GLB or glTF 2.0", per-engine defaults. The gap preventing a 5: the "Implementation Checklist" lists items to define without guidance on defining them, and the key detail (the decision table, per-engine structures) is delegated to reference files that are not present in the bundle, leaving the guidance partially incomplete.

Workflow Clarity

There is a coherent implicit sequence — settle the engine track, apply the Architecture Rules, work the "Define these before writing core code" checklist, then "Once the stack is clear, hand off to the runtime or asset specialist skill" — with clear entry (Use When) and exit (Do Not Stay Here When) conditions. No validation checkpoints exist, but the skill is architectural rather than a destructive or batch operation, so the cap does not apply; minor checkpoints (e.g. how to verify the architecture is settled) keep it at 4 rather than 5.

Progressive Disclosure

The body itself is well structured with a clear References section signaling six one-level-deep files, but none of the referenced paths (../../references/engine-selection.md, phaser-architecture.md, three-webgl-architecture.md, threejs-stack.md, react-three-fiber-stack.md, web-3d-asset-pipeline.md) exist in the bundle — the skill directory contains only SKILL.md. Navigation is therefore broken: the disclosure chain points at dangling files, which is worse than the 'minor organization gaps' of a 4 and best fits the 3 anchor (structure present but the reference layer fails).

Specificity

The description names a concrete action ("Set browser-game architecture before implementation") and enumerates specific deliverables — "engine choice, simulation and render boundaries, input model, asset organization, or save/debug/performance strategy" — which matches the 'several specific actions; minor gaps in coverage' anchor. It falls short of 5 because the coverage is a single action verb plus a domain list rather than multiple distinct concrete actions.

Completeness

It explicitly answers both questions: "Set browser-game architecture before implementation" (what) and "Use when the user needs engine choice, simulation and render boundaries, input model, asset organization, or save/debug/performance strategy" (when, with concrete trigger phrases). This directly matches the top anchor; nothing is left implicit.

Trigger Term Quality

"browser-game", "engine choice", and "save/debug/performance strategy" are relevant keywords, but the description omits the natural phrases and synonyms users would actually say — no "web game", "2D/3D", "Phaser", "Three.js", "React Three Fiber", or "WebGL", all of which the skill explicitly covers. This matches the 'some relevant keywords but missing common variations or synonyms' anchor rather than the 'good keyword coverage' anchor above.

Distinctiveness Conflict Risk

"browser-game architecture" is a clear niche with distinct pre-implementation triggers (engine choice, boundaries, input model, asset policy) that would not naturally fire for general web-dev, asset-only, or runtime-specific skills. The what/when scoping keeps conflict risk minimal, matching the 'clear niche with distinct triggers' anchor.