Conciseness

The body is efficient and assumes Claude's competence ('Vanilla TS conventions (PascalCase types, kebab-case files, use-* hooks) are table stakes — assume them'), with no padding of known concepts. Minor trimming is possible: 'The short version' recap and repeated invocations of the `naming` sibling discipline restate points already made, so it sits at anchor 4 rather than the fully lean anchor 5.

Actionability

Guidance is concrete and repo-grounded: a crisp decision heuristic ('if the filename is a noun ... the contents probably want to live under that noun ... If the file is named for its _location_ (`page.tsx`, `loader.ts`, `route.ts`), free exports are fine'), named example files (`editor/grida-canvas-utils/css.ts` paired with `css.test.ts`), a negative tell ('a directory whose `index.ts` is a wall of re-exports'), and a concrete co-location rule ('Co-locate tests as `*.test.ts` siblings'). Not 5 because there is no short code snippet showing the target namespace/class shape versus the anti-pattern, which would make the pattern directly copyable.

Workflow Clarity

This is a single-purpose decision-guidance skill, not a multi-step process, and its core decision rule (class/namespace vs free exports) is unambiguous with explicit scope boundaries ('UI glue, route handlers, one-shot scripts ... can be plain exports'). No destructive or batch operations exist, so no validation cap applies. Scored 4 rather than 5 because the guidance is presented as parallel sections rather than a single sequenced decision path, and the skill exceeds the under-50-line simple-skill exception.

Progressive Disclosure

The single-file body is well organized into clear sections with a summary, and its external links (naming, code-react) are one level deep and clearly signaled in prose. No bundle files exist, and the content is appropriately sized for one file, but there is no explicit pointers/section structure for deeper material, leaving it just below anchor 5's 'well-signaled one-level-deep references' organization.

Specificity

The description names the domain ('TypeScript code shape') and gives two concrete directives — 'Prefer one class or namespace per file ... over scattered free exports' and 'consolidate related code, don't fragment' — but phrases like 'the unit of code should be the unit of spec' and 'taste, not lint' are abstract, so coverage is not comprehensive. Anchor 3 ('1-2 concrete actions, but not comprehensive') fits better than 4, which expects several listed specific actions.

Completeness

Both what and when are explicit and concrete: the what is 'Prefer one class or namespace per file ... consolidate related code, don't fragment', and the when is 'Use when authoring TS in `editor/grida-canvas*`, `editor/lib/`, or `packages/*`' with concrete trigger phrases. Not 4 because the 'when' is not merely present but specific with explicit path-glob triggers.

Trigger Term Quality

Good natural keyword coverage: 'TypeScript', 'TS', 'authoring TS', 'class', 'namespace', 'test', plus concrete directory triggers 'editor/grida-canvas*', 'editor/lib/', 'packages/*'. A few natural terms a user might say are missing (e.g. '.ts files', 'module organization', 'file structure'), keeping it below the comprehensive synonym/extension coverage of anchor 5.

Distinctiveness Conflict Risk

Clear niche with minimal conflict risk: triggers are scoped to specific repo directories, and it explicitly delineates siblings — 'Sibling to the `naming` skill; React-specific shape lives in `code-react`'. The path-scoped trigger makes triggering for the wrong skill very unlikely.