Analyze Selective Testing

When your Xcode selective testing suddenly stops skipping tests and effectiveness tanks from 75% to 15%, this walks you through the diagnosis. It queries Tuist's test run data to count cache hits by target, compares hash changes between runs, and points you at the root cause, whether that's an Xcode version bump that invalidated everything or a core dependency change that cascaded. The analysis is methodical: pull test run JSON, calculate effectiveness percentages, diff target statuses between good and bad runs, then give you concrete next steps. It's built for the specific moment when your test suite that used to skip 60% of unchanged targets is suddenly running everything and you need to know why.

Install to Claude Code

npx -y skills add tuist/agent-skills --skill analyze-selective-testing --agent claude-code