The body is lean and assumes Claude's competence, listing protected files, rules, and anti-patterns with no padding or explanation of concepts Claude already knows; every section earns its place.

Concrete, executable guidance throughout: an authoritative file table, exact allowed node: built-ins, explicit anti-pattern imports to avoid, and a numbered procedure for adding new bootstrap utilities with a named test pattern.

The 'Adding New Bootstrap Utilities' section gives a clear numbered sequence with a regression-test checkpoint, and the rules section functions as a validation checklist before sweeping refactors; the prevention-over-detection note reinforces the feedback intent.

A single self-contained SKILL.md with well-organized sections and no bundle files; references to a test pattern (detect-squad-dir-zero-deps.test.ts) are inline signals rather than nested references, satisfying the simple-skill allowance.

Names a concrete domain (zero-dependency bootstrap files) and a specific constraint (never import npm packages or SDK code), but describes a single restriction rather than listing multiple distinct capabilities.

It states clearly what these files must never do, but there is no 'Use when...' clause or equivalent explicit guidance on when to invoke the skill, which caps completeness at 2 per the rubric.

Contains relevant technical terms ('bootstrap files', 'npm packages', 'SDK code') that an engineer might say, but lacks common natural variations a user would voice when needing this skill.

The niche is narrow and distinctive (zero-dependency bootstrap files in squad-cli) with triggers tied to a specific package boundary, making conflict with other skills unlikely.