Conciseness

The body is lean and assumes git competence — no concept explanations, dense classification table, purposeful Anti-patterns section — but safety guidance repeats across 'Never `--force` remove… without explicit user confirmation' (Hard rule 1), the step-5 comments, and the first anti-pattern. That trimmable redundancy fits the 'efficient; minor instances… could be trimmed' anchor (4) rather than the every-token-earns-its-place anchor (5).

Actionability

Fully executable throughout: `git worktree list --porcelain`, `git symbolic-ref refs/remotes/origin/HEAD`, `git merge-base --is-ancestor <branch> origin/<base>`, `gh pr list --state merged --head <branch> --json number`, and the exact remove/branch-delete commands with when-to-use-`-D` conditions. Commands are copy-paste ready and the classification table gives detection criteria for every case — matches the 5 anchor.

Workflow Clarity

A clear six-step sequence with explicit validation checkpoints throughout a destructive batch operation: `git fetch --prune origin` before merge checks, per-worktree classification before any action, one consolidated `AskQuestion` approval, safe `git branch -d` that 'refuses if unmerged' as a built-in guard, and a closing report of removals, skips, and failures. Validation is present and explicit, so the destructive-batch cap of 3 does not apply; the error-recovery reporting matches the 5 anchor.

Progressive Disclosure

No bundle files exist (references/, scripts/, assets/ absent) and the skill is a single well-sectioned document with clear headers (Hard rules, Workflow steps 1–6, Anti-patterns, Example session) — appropriate for a ~110-line procedural skill. Not a 5: at this length, the Example session and the base-branch fallback details are content that could live in a separate reference file, leaving SKILL.md a tighter overview.

Specificity

Quotes multiple concrete actions — 'Audits git worktrees and removes', 'merged into the base branch (including squash-merges via `gh`)', 'missing on disk', 'deletes the associated local branches and runs `git worktree prune`' — matching the comprehensive-coverage anchor (5). It goes beyond the 4 anchor by enumerating the exact safety criteria and follow-up actions rather than leaving minor gaps.

Completeness

Both what ('Audits git worktrees and removes the ones that are safe to delete… then deletes the associated local branches and runs `git worktree prune`') and when ('Use when the user asks to clean up worktrees…') are explicit and concrete, exactly matching the 5 anchor. Not a 4 because the 'when' clause lists specific trigger phrases rather than being merely adequate.

Trigger Term Quality

'Use when the user asks to clean up worktrees, prune worktrees, list stale worktrees, remove merged worktrees or branches, or reclaim disk space from old checkouts' covers natural phrasings with synonyms (worktrees, branches, checkouts, stale). It fits the comprehensive natural-terms anchor (5); no common user phrasing for this domain is missing.

Distinctiveness Conflict Risk

The git-worktree cleanup niche is distinct with domain-specific triggers ('worktrees', 'prune worktrees', 'merged worktrees or branches'), and even the broadest phrase ('reclaim disk space') is scoped to 'old checkouts'. Clear niche with minimal conflict risk — the 5 anchor; it does not overlap with generic file- or code-management skills.