How to review a commit with Codex

A backport or release handoff often depends on one recorded Git change. Codex commit review targets that change so feedback stays tied to a specific commit rather than the branch or uncommitted working tree.

The target SHA must resolve in the local repository. A rebase, squash, or amend creates a different commit identity, so review feedback belongs to the SHA actually inspected.

An installed, authenticated Codex CLI can review a commit from your existing checkout. Repository content may reach the configured provider, so only code you are authorized to share belongs in the review.

1. List recent commits from the repository containing the change.

   $ git log --oneline -n 2
   387121d Add average helper
   0310379 Add arithmetic helper

   If the commit exists only on a remote branch, its history must be fetched before it can be selected locally.

2. Resolve the selected commit to its full SHA.

   $ commit=$(git rev-parse --verify 'HEAD^{commit}')

   HEAD selects the current commit. For an older change, replace HEAD with its SHA or tag; the commit suffix rejects a name that does not resolve to a commit.

3. Inspect the selected commit's change summary.

   $ git show --stat --oneline "$commit"
   387121d Add average helper
    math_utils.py | 5 +++++
    1 file changed, 5 insertions(+)

4. Run a review of the selected commit.

   $ codex review --commit "$commit"

   Progress and the final review appear directly in the terminal. The review target is the change introduced by the selected commit. If authentication is missing, sign-in must be restored before another review.
   Related: How to check Codex login status
   Related: How to fix the Codex trusted-directory error

5. Read the terminal findings for the selected commit.

   The new average helper raises the wrong exception for its explicitly documented empty-input case.
   
   Review comment:
   
   - [P2] Raise ValueError for empty input before dividing — /work/example-app/math_utils.py:7-7
     For empty input such as `[]`, this expression divides by zero and raises `ZeroDivisionError`, contradicting the documented `ValueError` contract. Callers handling the promised exception will not catch it. Explicitly check for empty input and raise `ValueError` before dividing.

   A finding names the file, line range, and suspected defect for human assessment. A review with no findings does not prove the commit is free of defects.