Lists multiple specific concrete actions and rules: classes under 100 lines, methods under 5 lines, no more than 4 parameters, controllers instantiate only one object. Also names code review, refactoring, and code quality improvements as concrete actions.

Clearly answers both 'what' (applies Sandi Metz's four rules for maintainable OO code in Ruby) and 'when' (explicit 'Use when' clause with trigger terms like 'Sandi Metz', 'code quality', 'refactoring', or reviewing Ruby code for maintainability).

Includes strong natural trigger terms users would actually say: 'Sandi Metz', 'code quality', 'refactoring', 'Ruby', 'code review', 'maintainability'. These cover common variations of how users would phrase requests in this domain.

Highly distinctive due to the specific focus on Sandi Metz's rules, Ruby codebases, and the enumerated constraints. Unlikely to conflict with generic code review or refactoring skills because of the named methodology and language specificity.

Significantly verbose. The 'When to Use This Skill' section repeats the YAML description. Sections like 'Overview' explain what the rules are for (Claude already knows Sandi Metz's rules). The prioritization tiers, usage patterns, and refactoring strategies are largely things Claude already knows about Ruby refactoring. The 'Consider Context' section lists obvious exceptions. Much of this content doesn't add novel information beyond what Claude already possesses.

The code counting rules with Ruby examples are concrete and useful, and the RuboCop configuration is copy-paste ready. However, the refactoring strategies are abstract lists (e.g., 'Extract related methods into new classes', 'Apply patterns: Strategy, Decorator, Command, Facade') rather than concrete before/after code examples. The workflow says 'Show before and after code examples' but doesn't actually include any.

The workflow has clear numbered steps and multiple usage patterns (full codebase, specific file, refactoring assistance). However, there are no validation checkpoints or feedback loops — for instance, after refactoring there's no step to re-check that the refactored code still satisfies all four rules, and 'Verify that tests still pass' is mentioned but not given concrete commands or error recovery guidance.

References to 'references/rules.md' are clearly signaled and one level deep, which is good. However, no bundle files were provided, so we can't verify the reference exists. The main SKILL.md itself is quite long (~180 lines) with content that could be split out (e.g., the detailed refactoring strategies, code counting rules, and automation config could live in reference files), making the overview heavier than ideal.