Opus 5: How to Review Generated Code

When an AI agent rewrites eleven files for a one-line fix, the real cost shifts from writing to reviewing. Three defensive layers address this: steering with concrete path constraints, structured review using mutation testing and fresh-model passes, and a deterministic pre-write hook that blocks out-of-scope file edits entirely. Together they route machine-checkable problems away from human attention, leaving only real judgment calls on your desk.