Conciseness

The body is lean tables and code with no padding, but "Vite is a next-generation frontend build tool with fast dev server (native ESM + HMR)..." restates what Claude already knows, and the version/date header ("Based on Vite v8.3.5 (Rolldown-powered), generated at 2026-11-05") is time-sensitive detail not in a deprecated/old-patterns section. Anchor 4 fits: efficient with minor trimmable instances; not 5 because not every token earns its place.

Actionability

Fully executable, copy-paste-ready content: CLI commands ("vite build", "vite build --ssr"), a complete defineConfig example covering the common cases (alias, proxy, build target), and a concrete plugin list. Matches anchor 5; anchor 4 would imply gaps in the executable guidance.

Workflow Clarity

A lookup/reference skill with unambiguous topic-to-reference navigation and no destructive or batch operations, so no validation cap applies. Not 5 because multi-step processes like the Rolldown migration rely entirely on the external reference with no inline sequencing or checkpoints; not 3 because navigation is clear and nothing is ambiguous.

Progressive Disclosure

Clear overview tables with six well-signaled, one-level-deep references (all verified to exist and contain substantive content), while the small Quick Reference stays appropriately inline. Matches anchor 5; no buried or nested references.

Specificity

Lists four concrete capability areas ("Vite build tool configuration, plugin API, SSR, and Vite 8 Rolldown migration"), though as noun topics rather than action verbs and with gaps like dev server/HMR. Clearly above anchor 3 (more than 1-2 concrete items) but not anchor 5 (not comprehensive action coverage).

Completeness

Explicitly answers both: what ("Vite build tool configuration, plugin API, SSR, and Vite 8 Rolldown migration") and when ("Use when working with Vite projects, vite.config.ts, Vite plugins, or building libraries/SSR apps with Vite") with concrete trigger phrases. Matches the anchor 5 pattern; anchor 4 would require the 'when' clause to be less explicit or specific.

Trigger Term Quality

"Use when working with Vite projects, vite.config.ts, Vite plugins, or building libraries/SSR apps with Vite" covers good natural terms including the config filename. Not anchor 5 because common variations like "dev server", "HMR", or "build errors" are missing.

Distinctiveness Conflict Risk

Every trigger is Vite-branded ("Vite projects", "vite.config.ts", "Vite plugins") giving a clear niche with distinct triggers and minimal conflict risk, matching anchor 5 rather than anchor 4's minor overlap with closely related skills.