Isolate a technical problem into a minimal reproducible example ("reprex") and iterate fixes on that instead of inside the full application. Use when debugging a bug whose cause isn't obvious after a first look, when a failure only surfaces deep in a large pipeline / app / render, when the full-context test loop is slow, or before filing an upstream issue. Invoke explicitly with /reprexes.
Drive a pull request to a clean review verdict by looping request-review → address every finding → re-request-review until there are zero flagged items. Use when asked to "iterate until clean", "address the review comments", "@claude review again and fix what it finds", or after opening a PR you want carried all the way to mergeable. Handles the @claude bot reviewer and human reviewers.