Conciseness

The body stays lean and assumes Claude's competence: every section teaches gh-stack-specific behavior Claude cannot know (e.g. "`sync` exits 0 with 'Sync aborted' when the local and GitHub stacks diverge", exit codes 2/3/7/8/10, the rerere pre-setup) rather than re-explelling general git or PR concepts. Nothing reads as padding; the one general-knowledge touch ("GitHub refuses self-approval") is a one-clause justification for the script's behavior, not an explanation.

Actionability

Every instruction is a copy-paste-ready command with its arguments and exit semantics: `bash <skill-dir>/status.sh [pr-number | pr-url | branch]`, `gh stack submit --auto --open`, `gh stack rebase --continue # repeat until it exits 0`, `gh pr edit <pr> --title <title> --body-file <file>`, `git config rerere.enabled true`. The common cases (status, sync, watch, conflict, approve, build) each have a complete runnable path, including flag variants (`--interval`, `--timeout`, `--grace`, `--prune`, `--dry-run`).

Workflow Clarity

The update flow is a numbered sequence with explicit validation and feedback loops: rerun `status.sh` and show it as "the proof the sync landed", `watch.sh` polls until checks settle, and the conflict loop is resolve → `git add` → `rebase --continue` until exit 0 → `push` → rerun the report. Destructive/batch operations are gated: "Confirm before these" requires echoing scope and merge method back to the user, and approve distinguishes the go-ahead from status-only requests via `--dry-run`, so the batch/destructive cap does not apply.

Progressive Disclosure

Structure is good: three one-level-deep scripts (`status.sh`, `watch.sh`, `approve.sh`) are clearly signaled with usage lines and comments, and flag lists are deferred to `gh stack <command> --help` instead of being inlined. Minor gap: the exit-codes table and the TUI-trap details are reference-style material inlined in SKILL.md, and there is no `references/` or `scripts/` bundle listing to aid discovery of the scripts beyond their in-text mentions.

Specificity

It enumerates concrete capabilities in third person — "find a PR's stack, report and update what is stale, read each layer's checks, resolve conflicts, approve the stack, add a PR on top, split work into a stack, merge" — which comprehensively mirrors the body's workflows. This matches the 5 anchor (multiple specific concrete actions, comprehensive) rather than 4, which would imply minor coverage gaps; none are evident against the body.

Completeness

Both what and when are explicit: the action list answers what the skill does, and "Use whenever a PR or branch's base is not trunk, or for "stack", "PR on top of", "restack", "approve the stack"." provides concrete trigger phrases. This is a direct match for the 5 anchor.

Trigger Term Quality

Good natural-phrase coverage: "stack", "PR on top of", "restack", "approve the stack", plus the situational "base is not trunk" trigger. A few plausible synonyms are absent (e.g. "stacked PRs", "chained/dependent PRs"), which keeps it at the 4 anchor (good coverage, a few natural terms missing) rather than the 5 anchor's comprehensive synonym coverage.

Distinctiveness Conflict Risk

A clear niche — stacked PRs via the `gh stack` extension — with a precise mechanical trigger ("a PR or branch's base is not trunk") that a general PR skill would not claim, minimizing overlap. Fits the 5 anchor (clear niche, distinct triggers, minimal conflict).