Conciseness

Telegraphic bullets ("Enums: Literal unions or `as const`. **No runtime `enum`**.") state project standards without re-explaining TypeScript concepts Claude already knows. Every token carries a rule or an example; only the "Priority: P0 (CRITICAL)" heading is arguably filler, which does not drop it below anchor 5.

Actionability

Concrete, executable guidance throughout: specific syntax (`?.`, `??`, `satisfies`, `string & { __brand: 'Id' }`), a runnable code block, and a named verification tool (`getDiagnostics` via typescript-lsp MCP). Minor gaps — e.g. no tsconfig example for "strict: true" and no narrowing example to complement the "no `!`" rule — keep it at anchor 4 rather than 5.

Workflow Clarity

As a single-purpose standards skill, the action is unambiguous (apply the listed rules), and the Verification section provides an explicit checkpoint: "call `getDiagnostics` ... to confirm no type errors before finalizing", with clear scoping of when it applies. It is a rule reference rather than a sequenced multi-step workflow with recovery steps, so it fits anchor 4 rather than 5.

Progressive Disclosure

The ~60-line body stays an overview: testing gotchas are pushed to references/TESTING.md and advanced/utility patterns to references/REFERENCE.md, both verified to exist, clearly signaled with markdown links, and only one level deep. This matches the anchor-5 pattern of a clear overview with well-signaled references.

Specificity

"Apply modern TypeScript standards for type safety and maintainability" names the domain but the action itself is abstract — no concrete operations like "define discriminated unions" or "configure strict mode" are listed. It sits above anchor 2 (more focused than "Processes PDF files") but lacks the list of specific actions needed for anchor 4.

Completeness

Both parts are present: the what ("Apply modern TypeScript standards for type safety and maintainability") and an explicit when ("Use when working with types, interfaces, generics, enums, unions, or tsconfig settings"). The when clause is strong with concrete triggers, but the what is abstract, so it does not clearly match anchor 5's fully concrete example.

Trigger Term Quality

"types, interfaces, generics, enums, unions, or tsconfig settings" are natural terms users would say when needing this skill, and "tsconfig" is distinctive. It falls short of anchor 5 because file extensions (.ts/.tsx) and common variations like "strict mode" or "type guards" are missing.

Distinctiveness Conflict Risk

"tsconfig", "generics", and "enums" clearly signal the TypeScript niche, keeping conflict risk low. There is minor overlap risk with closely related skills (general JavaScript style or linting skills), which fits anchor 4 rather than the clean niche of anchor 5.