Conciseness

The body is almost entirely executable commands plus genuinely non-obvious domain guidance (rerere recovery, filtered machine-state files, the worktree fetch caveat), with no padding and no explanation of concepts Claude already knows. It matches anchor 5 (lean, every token earns its place); anchor 4 would require some trimmable over-explanation, which is absent.

Actionability

Context gathering, divergence analysis, simple/onto rebase, and push are given as exact runnable commands. However the cherry-pick strategy is only described ("create `<subject>__cherrypick__` from `target_ref` and cherry-pick subject commits oldest-first") without executable commands, and `git branch --set-upstream-to="origin/${subject}"` silently assumes the remote branch already exists. This is anchor 4 (mostly executable, minor gaps) rather than anchor 5 (copy-paste ready across all paths).

Workflow Clarity

The sequence has strong checkpoints for a destructive workflow: dirty-tree stop condition, analysis shown before proceeding, conflict-marker verification before `--continue`, rerere-based recovery, and `--force-with-lease` for the push. But the numbered workflow skips step 4 entirely (it jumps from 3 to 5), a real sequencing defect that keeps it below anchor 5; it stays above anchor 3 because validation for the destructive and batch operations is explicitly present.

Progressive Disclosure

The skill is a single well-organized file with no bundle files, and the Workflow sectioning is clear. At roughly 75 lines it exceeds the simple-skill threshold, and the strategy-selection table and conflict-resolution heuristics are cohesive but arguably separable into a reference file. This lands on anchor 4 (good structure, minor organization gaps) rather than anchor 5 (clean overview with well-signaled split references).

Specificity

"Rebase the current branch onto a target branch" names the domain and one concrete action; "using safety checks and an appropriate rebase strategy" describes manner rather than enumerating additional concrete actions (conflict resolution, push, tracking are absent). This matches anchor 3 (domain plus 1-2 concrete actions) rather than anchor 4, which expects several listed specific actions.

Completeness

It explicitly answers both questions: the "what" ("Rebase the current branch onto a target branch using safety checks and an appropriate rebase strategy") and the "when" with concrete trigger phrases ("Use when invoked as `$git-rebase` or when the user asks to update/rebase a branch"). This is a clear anchor-5 match; anchor 4 would require the "when" clause to be less explicit.

Trigger Term Quality

"Use when invoked as `$git-rebase` or when the user asks to update/rebase a branch" captures the natural keyword "rebase" plus the synonym "update a branch". It falls short of anchor 5 because common variations like "pull in changes from main" or "bring my branch up to date" are not covered.

Distinctiveness Conflict Risk

The description is tightly scoped to git rebasing, a clear niche with distinct triggers ("rebase", "update/rebase a branch"), so it is unlikely to fire for unrelated skills. It matches anchor 5 (clear niche, minimal conflict risk) and not anchor 4, which anticipates overlap with closely related skills.