# M03-L03 — Branch and review an agent change

**Outcome:** Review a bounded change and reject an unrelated edit before integration.

**Start:** M03-L02 and a disposable CP01 practice checkout.

Start clean and create a branch for one task using `git switch -c feature/report-origin`. A branch names a line of history; it does not automatically isolate unexplained uncommitted work. Inspect status and baseline first. [Git branching](https://git-scm.com/book/en/v2/Git-Branching-Basic-Branching-and-Merging)

Request a README-only clarification that the baseline prints synthetic input. Preserve the firmware, host sample value, dependencies, and build commands. Ask for the actual diff and checks performed. Inspect the agent's action record and changed-file list.

If the agent stays within scope, use the labeled seeded review candidate in Chapter 7 resources to practice partial rejection. That candidate keeps the useful README sentence but changes the fixed synthetic temperature in `host/replay.cpp` from 25.00 to 30.00. This is a constructed exercise, not a fabricated agent mistake. CP01 has no threshold policy yet.

Review every hunk against the brief. Accept the explanatory origin sentence if accurate; reject the unrelated sample-value change. Correct only the unwanted edit, inspect the final diff, and run the applicable replay if source was touched. Write finding, evidence, consequence, and requested correction.

Commit and push the reviewed feature branch to your private practice remote. Open a pull request targeting main and inspect its Files changed view. The hosted diff should match the locally reviewed result. A solo review is a self-review, not an independent human review. [Reviewing a pull request](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/reviewing-proposed-changes-in-a-pull-request)

Describe the concrete problem, resulting behavior, and actual validation. Keep any unperformed check explicitly pending. A pull request organizes review; its existence is not proof that the change is correct.

![A feature develops from a baseline, is reviewed and merged, and a later fault can be reversed by a new commit while the faulty commit remains in history.](../../../../book/figures/D07.png)

*D07. A feature develops from a baseline, is reviewed and merged, and a later fault can be reversed by a new commit while the faulty commit remains in history.*

## Practice and completion

Complete the [exercise](exercise.md), then compare your artifact with the separately distributed instructor answer. A lesson acknowledgment records your own progress; it does not certify that a physical test occurred.

## Reading and figures

[Chapter 7](../../../../book/chapters/ch07/chapter.md). Resources: [Constructed review candidate](../../../../book/chapters/ch07/resources/review-candidate.md). Figure references: SS07-01–03; D07.