Conciseness

Mostly efficient, but it restates the Turbopack-is-default fact three times (intro, 'When to Use', 'How It Works'), lists trivial known commands (`next dev`, `next build`, `next start`), and repeats time-sensitive hedged claims ('check the docs for your version', 'check the official Next.js docs for your version') that could be consolidated. Not score 4 because the redundancy goes beyond minor trimmable instances; not score 2 because there is no padded conceptual tutorial text.

Actionability

Some concrete guidance exists (`--webpack` flag, proxy.ts vs middleware.ts naming, cache location under `.next`, the explicit 'Do not flag proxy.ts' instruction), but key details are deferred with vague hedges like 'enable via config or experimental flag (see Next.js docs for your version)' and 'may use Turbopack or webpack depending on Next.js version; check the official docs'. Not score 4 because several actionable claims stop short of the actual command/config; not score 2 because the middleware naming and bundler-selection guidance is genuinely concrete.

Workflow Clarity

As a decision-guide skill, its conditions are clearly sequenced: when to use Turbopack vs webpack, when to use proxy.ts vs middleware.ts, plus a diagnosis path ('If dev is slow, ensure you're on Turbopack...'). Not score 5 because the version-dependent branches resolve to 'check the docs' rather than a decisive checkpoint, leaving minor gaps; not score 3 because each decision point has an explicit condition and outcome rather than vague steps.

Progressive Disclosure

The body is ~50 lines with well-organized sections (When to Use, How It Works, Examples, Middleware File Naming, Best Practices), no bundle files exist, no references are dangled to nonexistent files, and the single external link (Next.js proxy docs) is clearly signaled at one level of depth. This matches the under-50-line simple-skill case where well-organized sections alone earn a 5.

Specificity

It lists several concrete capabilities: 'incremental Rust bundling, file-system caching, faster dev startup and HMR, Turbopack vs webpack tradeoffs, and the middleware.ts to proxy.ts filename change'. Not score 5 because these are topic nouns rather than executable action verbs (no 'diagnose/choose/review'-style what-it-does verbs in the what-clause); not score 3 because coverage is broad and each named capability is concrete, not generic.

Completeness

It explicitly answers both what ('Next.js 16+ and Turbopack guidance — incremental Rust bundling, file-system caching...') and when ('Use when developing or debugging Next.js 16+ apps, diagnosing slow dev startup or hot reload, choosing between bundlers, or reviewing middleware/proxy file naming') with concrete trigger phrases. This matches the anchor-5 example structure directly; score 4 would require the 'when' clause to be less explicit, which it is not.

Trigger Term Quality

Good natural keyword coverage: 'Next.js 16+ apps', 'Turbopack', 'slow dev startup', 'hot reload', 'choosing between bundlers', 'middleware/proxy file naming' — phrases a user would plausibly say. Not score 5 because common synonyms/extensions (e.g. 'webpack dev server slow', 'HMR', '.next cache', 'build times') are only partially covered; not score 3 because both the primary terms and several natural variations are present.

Distinctiveness Conflict Risk

Clear niche (Next.js 16+/Turbopack/proxy.ts) with distinct triggers like 'Turbopack vs webpack tradeoffs' and 'middleware.ts to proxy.ts filename change' that no general web-dev or Next.js-general skill would claim as its core. Not score 4 because the version-pinned terms make overlap with adjacent skills minimal rather than merely minor.