Review diffs before commit
Accept the change you asked for, not every change present
After this, you'll be able to inspect a Codex diff, separate intended edits from incidental changes, and stage only accepted work.
Before you start
Complete Run the proof loop first.
The idea
Diff review is where you take ownership back. Codex can make the patch, but you decide what belongs in the commit.
Here is the before and after: before, Codex is guessing from a loose request. After, you can inspect a Codex diff, separate intended edits from incidental changes, and stage only accepted work.
Now try it use the exercise prompt on one real repo task. Keep the output small enough to check before you accept the change.
You are ready when the Codex action, boundary, and proof all match the task.
Try it (14 min)
Watch out for
- Staging every file because the main behavior works.
- Ignoring package manager lockfile changes.
- Accepting test edits that reduce coverage.
- Letting generated files into the commit without the generator command.
Paste this into Claude
Review this Codex diff summary: Task: [original task] Changed files: [paste file list] Proof run: [paste commands and results] Unexpected changes: [paste any surprise, or write none] Return: 1. Files to stage. 2. Files to revert or inspect. 3. One question for Codex if the diff is unclear. 4. Commit message only if the diff is ready.
What a good response looks like
Stage src/app/profile/page.tsx and src/lib/profile.ts. Inspect package-lock.json because dependency changes were not in scope. Ask Codex why tests changed. Do not commit until the package lock reason is accepted or reverted.
What good looks like
- Intended files are separated from incidental changes
- Generated, dependency, auth, data, or config changes are inspected
- The proof matches the staged change
- The commit message is withheld when the diff is not ready
When this breaks
- Breaks when an unrelated cleanup ships with the bug fix and creates a second regression.
- Breaks when a generated artifact is hand-edited and later overwritten.
AI can help with this
Use Codex to help you you can inspect a Codex diff, separate intended edits from incidental changes, and stage only accepted work. Start with the exercise prompt and your real input. Ask for one draft, then check it against this proof: Intended files are separated from incidental changes. Accept only the version you can verify yourself.
You can now
You can review behavior, scope, and proof
- You can stage part of a Codex change
- You can spot incidental churn
- You can withhold commit until the diff is ready
Key takeaways
Codex writes the patch. You own the commit. Stage only the change that solves the task and passes proof.
- Review behavior first, scope second, proof third.
- Good and bad changes can appear in the same diff.
- Generated and dependency files need a reason.
- A commit should be smaller than the agent run when the run wandered.
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