Names the domain (A/B tests) and mentions some actions (setting up, gates for hypothesis, metrics, execution readiness), but doesn't list comprehensive concrete actions like 'define control groups', 'calculate sample sizes', or 'analyze results'.

Describes what it does (structured guide for A/B test setup with gates) but completely lacks a 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill.

Includes 'A/B tests' which is a natural term users would say, but misses common variations like 'split testing', 'experiment', 'variant testing', 'conversion testing', or 'multivariate test'.

The focus on A/B tests with mandatory gates provides some distinctiveness, but 'hypothesis' and 'metrics' are generic terms that could overlap with general experiment planning or analytics skills.

The content is extremely lean - no unnecessary explanations of what A/B testing is or how statistics work. Every line serves a purpose: scope, prerequisites, and navigation to sub-skills.

The skill provides no concrete guidance, code, commands, or examples. It's entirely a table of contents with vague bullet points like 'Prevents peeking' without explaining how or what to do.

The numbered sub-skills suggest a sequence (1-11), and 'Hard Gate' labels indicate checkpoints. However, the actual workflow steps, validation criteria, and feedback loops are entirely delegated to sub-files with no summary of what each gate requires.

References are one level deep and clearly linked, which is good. However, the main skill is essentially empty - it's all navigation with no substantive overview content. Users cannot understand the process without clicking through 11 separate files.