The body is lean and assumes Claude's competence — it never explains what a changelog, milestone, or PR is — and every section (Inputs, Procedure, Format Rules, Validate) earns its place without padding.

Provides executable GitHub search query strings, a concrete classification table with explicit criteria, and a copy-paste-ready markdown template with precise format rules (bullet styles, blank-line rules, linking policy).

A clearly sequenced four-step workflow (Gather, Classify, Write, Validate) with an explicit validation step containing concrete checkpoints (positioning, link correctness, no duplicates); validation is present, so it is not capped at 2.

Self-contained single-task skill with no bundle files needed; content is well-organized into clearly signaled sections with no nested references and nothing that would benefit from being split out.

Names a concrete deliverable and domain ('Write a CHANGELOG.md entry for a new extension release') but lists a single action rather than multiple specific actions, matching the 'names domain and some actions, but not comprehensive' anchor.

Clearly answers both what ('Write a CHANGELOG.md entry for a new extension release') and when via an explicit 'Use when:' trigger clause, plus required inputs; satisfies the score-3 anchor.

The 'Use when:' clause lists natural user phrases — 'writing changelog, updating changelog, adding release notes, preparing a release, documenting milestone changes' — giving good coverage of terms users would actually say.

Targets a clear niche — changelog generation for extension releases scoped to a GitHub milestone — with distinct triggers, making overlap with other skills unlikely.