Ad Test Designer Designs paid-ad creative/landing A/B/n and incrementality tests and reads them out: hypothesis, variant matrix, sample-size/duration/power plan, effect size, uncertainty, practical-effect status, and guardrail state. This skill owns experiment design + statistical interpretation . It may apply an owner-approved, precommitted action rule, but it never treats a p-value or helper output as an automatic business decision. It does not produce variants ( ), read back one already-shipped change ( ), or do cross-channel reporting ( ). Quick Start Skill Contract - Expected output : a…