Conciseness

The body is lean and assumes Claude's competence — it never explains what a rebase is or how git works, and directives like "Do not describe a PR as current merely because Git reports no conflicts" and "Age alone is not evidence, and sunk effort is not a reason to keep a PR alive" each earn their tokens. Every section adds judgment guidance Claude would not reliably produce on its own, matching anchor 5 ("Lean and efficient; assumes Claude's competence; every token earns its place").

Actionability

The guidance is mostly executable for an instruction-only skill: concrete commands ("`--force-with-lease` against the head SHA observed before the rebase", "`git range-diff`"), a precise six-step rebase procedure, and three crisply defined dispositions (MODERNIZE/REWORK/CLOSE). It falls short of anchor 5 only because the PR-intake phase gives no example commands for fetching or inspecting the PR (e.g., gh pr view or fetching the PR head ref), leaving minor gaps.

Workflow Clarity

The process is explicitly sequenced — establish intent, check what changed around it, choose a disposition, then a numbered rebase workflow — with validation checkpoints (range-diff comparison, focused checks, distinguishing real from pre-existing failures) and error-recovery loops ("If the lease fails, fetch and reassess rather than overwriting new work"; a conflict revealing an architecture disagreement means "stop and reconsider the disposition"). The destructive force-push operation is fully guarded, matching anchor 5.

Progressive Disclosure

The single ~95-line file is well-organized into scannable sections (Guardrails, Establish intent, Check what changed, Disposition, Rebase, Report) with nothing inlined that clearly belongs in a separate file, and the cross-reference to the `leaving-pr-comments` skill is clearly signaled. It scores 4 rather than 5 because there are no bundle files or referenced deep-dive material at all, and the body exceeds the under-50-line simple-skill case the rubric exempts for a top score.

Specificity

"For getting old prs up to date" names the domain (old pull requests) but the stated action is generic — no concrete capabilities such as rebasing, resolving conflicts, validating continued relevance, or force-pushing are listed. This matches anchor 2 ("Names the domain but actions are minimal or generic") and falls short of anchor 3, whose example names 1-2 concrete actions; "rebase" appears only in the when-clause, not as a described capability.

Completeness

The when is explicit ("Use when asked to rebase a pr or 'modernize'"), but the what — "For getting old prs up to date" — is vague and states no concrete capability. It sits between anchor 3 (clear what, missing when) and anchor 4 (both present, one less explicit); because the what is too thin to convey what the skill actually does, it lands at 3 rather than 4, and it is clearly above anchor 2 since an explicit 'Use when' trigger clause is present.

Trigger Term Quality

"Use when asked to rebase a pr or 'modernize'" supplies two natural phrases users would actually say, but coverage stops there — common variations like "update an old PR", "stale PR", "outdated branch", or "catch up with main" are absent. This fits anchor 3 ("Some relevant keywords but missing common variations or synonyms") better than anchor 4, which expects broader keyword coverage.

Distinctiveness Conflict Risk

"old prs" and "rebase a pr" carve out a fairly specific niche, but the bare quoted trigger "modernize" is ambiguous — users asking to modernize a codebase, dependencies, or infrastructure would also match it, creating real overlap risk with unrelated skills. This matches anchor 3 ("Somewhat specific but could still overlap with similar skills"); it does not reach anchor 4 because that ambiguity is not minor.