Conciseness

The body is lean and assumes Claude's competence: no explanations of known concepts, no padded sections, and every rule carries a specific non-obvious value ("Elevation is 30 degrees", "stiffness 64, damping 14.2 and a 0.04 s stagger", "Clamp the frame step to 1/20 s"). Anchor 4 would require trimmable over-explanation, and none is present.

Actionability

Fully executable guidance: runnable commands ("node templates/build.mjs", "node --test templates/model.test.mjs"), named kit functions ("inkSolid", "silhouetteSvg", "castShadowSvg", "glassSvg", "pillSvg", "wobbleFilter"), exact constants, and concrete URL behaviors ("reads ?labels=0"). Per the code-vs-instruction scoring note, the absence of inline code blocks is not penalized because a working starter template is provided and every instruction is concrete.

Workflow Clarity

The Method section gives 12 clearly sequenced steps, step 12 is an explicit headless-browser verification step, and "Check before you finish" is a 16-item validation checklist with feedback loops ("Rebuilding produces no diff", "scenario sweep runs every config to the end with zero console errors", "line-end check reports zero loose ends"). This matches anchor 5's sequence-plus-validation-plus-checklist pattern.

Progressive Disclosure

The body is a true overview: a 12-step method and rules inline, with all detail split into six one-level-deep reference files (references/concept.md, state-model.md, geometry.md, colour-and-ink.md, live.md, verify.md) that all exist in the bundle and are each described with their scope in the Files section. Cross-references between reference files are peer-level, not nested, so navigation stays one level deep.

Specificity

Lists several concrete actions — "Builds an interactive isometric machine page", "A pure, tested state model drives the motion, the readouts and the copy", "The page has controls and a verification loop" — but the actions are slightly more abstract than anchor 5's fully tangible action lists. Not 3 because it names more than 1-2 concrete actions with a clear domain; not 5 because coverage is not fully comprehensive in tangible, verbatim-executable terms.

Completeness

Explicitly answers both questions: the "what" ("Builds an interactive isometric machine page", "A pure, tested state model drives the motion, the readouts and the copy") and the "when" ("Trigger phrases: ..." listing six concrete triggers). This matches anchor 5's pattern of clear what-and-when with concrete trigger phrases; a 4 would require the when to be less explicit.

Trigger Term Quality

Six natural trigger phrases — "isometric explainer", "machine explainer", "explain this as a machine", "interactive isometric figure", "explorable explainer", "show how it works inside" — comprehensively cover the synonyms a user would plausibly say for this niche. Anchor 4 would require missing natural variations, and none are apparent for this domain.

Distinctiveness Conflict Risk

The niche is clear and the core triggers ("isometric explainer", "machine explainer", "interactive isometric figure") are distinct, but broader phrases like "explorable explainer" and "show how it works inside" could overlap with general interactive-explainer or visualization skills. Mostly distinct with minor overlap risk against closely related skills fits anchor 4; anchor 5 would require minimal conflict risk across all triggers.