Stage 4 · Lesson 1 of 7
Reading every diff
A shows exactly which lines were added, removed or changed. It is the only honest record of what the tool did; the tool's own summary can say "fixed the bug" when the change also deleted a check. Read the list of changed files first: anything you did not expect is a warning.
Then read each file line by line. In Claude Code, /diff reviews the working tree. In , you can accept all changes with Cmd+Enter or reject them with Cmd+Shift+Backspace, but only after reading.
In , the Changes editor shows each edited file. And git diff works everywhere. Stage only what you reviewed with git add -p.
Common trapaccepting everything because the summary sounded right, without opening a single file.
A question to check yourself, an AI practice session and 2 cheat sheet entries come when you add the roadmap to your account. Add it
Resources for this stage
Start with
- GuideFreeGoogle Engineering Practices
Google · Intermediate
Google's free code review guide: what reviewers look for and how to write review comments