Conciseness

The body is dense with operational specifics and explains nothing Claude already knows, but a few instances could be trimmed — e.g., "do not assume that `skills_cli.py` or another executable is beside this file" and several wordy Safety bullets — placing it at "efficient; minor instances of over-explanation" rather than the every-token-earns-its-place level of a 5.

Actionability

Fully executable copy-paste commands for every operation (`list`, `search flutter`, `install flutter-expert`, `install --bundle core-dev`, `doctor`, `installed`, `update`) plus complete `AG_SKILLS_DIR` env-var examples cover all common cases, matching the score-5 anchor; score 4 would require gaps in coverage.

Workflow Clarity

The five-step Instructions sequence includes explicit validation checkpoints ("Check the resolved destination with `doctor`... before replacing them", "Do not report success after a nonzero exit status") and error-recovery loops (failed copies leave installation intact, recovery path, stale-lock verification) for the destructive replace operations — matching the score-5 anchor; score 4 would require minor validation gaps.

Progressive Disclosure

The skill is self-contained with no bundle files, well-organized into clearly headed sections (Use when / Do not use / Instructions / Commands / Installation scope / Safety), and its only external references are clearly signaled one-level-deep links to official docs — matching the score-5 anchor for clear overview and easy navigation.

Specificity

"Searches, installs, updates, and lists skills" names four concrete third-person actions covering the full management lifecycle, anchored to the named "Antigravity Skill Vault" — comprehensive coverage matching the score-5 anchor, with no gaps that would justify a 4.

Completeness

The description explicitly answers both "what" (searches, installs, updates, and lists skills from the vault) and "when" ("Use when choosing or managing workspace or global skills through the npm CLI") with concrete trigger phrases, matching the score-5 anchor exactly.

Trigger Term Quality

Natural terms like "skills", "installing", "searches", and "workspace or global skills" are present, but common synonyms such as "add", "browse", or "find skills" are missing, placing it at "good keyword coverage; a few natural terms missing" rather than the comprehensive synonym coverage of a 5.

Distinctiveness Conflict Risk

"Antigravity Skill Vault" and "through the npm CLI" establish a clear niche with distinct triggers and minimal conflict risk against generic skill managers; the vault name and CLI scope prevent the minor overlap that would justify a 4.