Conciseness

The ~25-line body is lean with zero padding: a pointed pointer to the detailed guide ("Read the detailed guide before executing this skill... Treat its safety, prerequisites, and validation requirements as mandatory"), scoping bullets under "When to use d3.js", and a short limitations section. No concepts Claude already knows are explained, and every line carries scope or navigation information. It is not below 5 because nothing here could be trimmed without losing signal.

Actionability

The guidance that is present is concrete and unambiguous — read references/detailed-guide.md first, treat its validation requirements as mandatory, prefer Three.js for 3D, stop if inputs are missing — but all executable substance (code, commands, steps) is delegated to the reference file, leaving the body itself with directional rather than executable guidance. This matches anchor 3 (some concrete guidance but incomplete, key details missing) rather than 4, whose body-level content would itself be mostly executable.

Workflow Clarity

The only sequence the body expresses is 'read the guide, then follow it', with validation present but implicit — "Treat its safety, prerequisites, and validation requirements as mandatory" names validation without any checkpoint, and "Do not treat the output as a substitute for environment-specific validation, testing, or expert review" is a caveat rather than a step. No destructive or batch operations are involved, so the cap does not apply, but the actual multi-step workflow lives entirely in the reference, leaving the body at anchor 3 (sequence present, checkpoints missing/implicit) rather than 4.

Progressive Disclosure

Scored against the actual bundle: the body cleanly signals one reference (references/detailed-guide.md) and correctly inlines nothing that belongs in a separate file, but the other three reference files (d3-patterns.md, scale-reference.md, colour-schemes.md) and all three assets are never mentioned in SKILL.md — they are only discoverable two levels deep, inside the guide's 'Resources' section, which also misnames the assets ('chart-template.js'/'interactive-template.js' vs. the actual .jsx files). This is better than anchor 2 (nothing is wrongly inlined) but short of anchor 4's 'references mostly clear' because most of the bundle is unindexed from the entry point and one documented path is wrong.

Specificity

The description names the domain ("interactive data visualisations using d3.js") but the only action is the generic "provides guidance for creating" — no concrete capabilities (e.g., chart types, transitions, interactions) are listed. It sits between anchor 1 (no domain) and anchor 3 (1-2 concrete actions): the domain is named clearly, but the action described is entirely generic.

Completeness

There is a recognizable 'what' (guidance for creating d3.js visualisations) but the 'when' is entirely absent — no "Use when..." clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines. It is not 2 because the 'what' is domain-specific rather than vague, and not 4 because no use-when guidance exists at all, explicit or otherwise.

Trigger Term Quality

"d3.js" and "interactive data visualisations" are relevant keywords a user might say, but common natural terms are missing: chart, graph, plot, dashboard, the "d3" short form, and the American spelling "visualizations". This matches anchor 3 (some relevant keywords, missing common variations/synonyms) rather than anchor 4's good coverage.

Distinctiveness Conflict Risk

"using d3.js" carves out a clear niche with distinct triggers, giving mostly-distinct positioning with only minor overlap risk against general charting/visualization skills. It falls short of anchor 5 because, without any 'use when' scoping, a generic 'make me a chart' request could plausibly match this and a general dataviz skill.