Conciseness

Every line carries project-specific rules Claude could not infer: placement boundaries, tooling conventions ("class-variance-authority", "cn()"), the typing rule, and downstream-consumption caveats. There is no explanation of concepts Claude already knows — a clean match for 'Lean and efficient; assumes Claude's competence; every token earns its place'.

Actionability

Concrete, executable guidance throughout: exact paths ("packages/ui/src/index.ts", "styles.css"), copy-paste validation commands ("cd packages/ui && npm run build"), and a three-way placement decision rule. It stops short of level 5 because some instruction is deferred to the repo itself ("Follow the existing Radix-wrapper and typed-export patterns") and 'when appropriate' hedges the cva rule — minor gaps the level-4 anchor describes.

Workflow Clarity

This is a simple, single-purpose rules skill, so the simple-skill exception applies: the action is unambiguous (edit within scope, respect the rules, then validate), and the Validation section gives explicit commands with conditional escalation checkpoints ("Also validate packages/dashboard/ when the changed component is used in the dashboard"). No destructive or batch operations, so no validation cap applies.

Progressive Disclosure

The body is 43 lines with no external references needed and no bundle files exist, so per the rubric's guideline for short skills, well-organized sections alone qualify: Scope, Working Rules, and Validation are cleanly separated and each is scannable.

Specificity

The domain is clearly named ("InsForge's reusable UI package") and it lists concrete objects of work ("design-system primitives, exports, styles, and package-level component behavior"), but the action verbs stay generic — "contributing" and "editing" — without naming what is actually done (e.g., adding components, exporting them, maintaining variants). This matches the anchor 'Names domain and 1-2 concrete actions, but not comprehensive' and is below level 4, which expects several specific actions.

Completeness

Both halves are present: what ("editing design-system primitives, exports, styles, and package-level component behavior") and an explicit when ("Use this skill when contributing to InsForge's reusable UI package"). It is not level 5 because the 'when' clause is a single trigger with no concrete trigger-phrase variations (e.g., 'when the user mentions the design system or packages/ui').

Trigger Term Quality

Good natural-term coverage for the niche: "UI package", "design-system primitives", "exports", "styles", "monorepo", "maintainers" — phrases a contributor would plausibly say. It falls short of level 5 because common variations like "design system", "shared components", or the literal path "packages/ui" are absent.

Distinctiveness Conflict Risk

It is tightly scoped to one named repository's UI package ("in the InsForge monorepo", "for maintainers"), giving it a clear niche with distinct triggers and minimal risk of firing for unrelated skills — a clean match for level 5.