Claude CodeBeginner

How to Review Your Own Diff Before Committing with Claude Code

Run a focused self-review of your staged changes with Claude Code to catch bugs and leftovers before they land.

6 minBeginner

A quick self-review before you commit catches the embarrassing stuff: a stray console log, a flipped condition, a TODO you meant to finish. Claude Code can read your staged diff and flag issues without you opening a pull request. Keep the review scoped to the diff so the feedback is about what you actually changed.

What you need

Claude Code in a git repository
Changes you have staged with git add
A couple of minutes before you commit

Step 1: Stage the changes you intend to commit

Stage exactly what is going into the commit. Reviewing the staged diff rather than the whole working tree keeps the review focused on this change.

zsh - my-app

$git add src/auth/

$git diff --cached --stat

src/auth/session.ts | 34 ++++++---

src/auth/login.ts | 12 +++--

Step 2: Ask Claude to review the staged diff

Ask for a review of the staged changes only, focused on correctness and leftovers. Naming what you care about, bugs and debug code, gets you a tighter list than a vague request.

Claude Code

You

Review my staged changes (git diff --cached). Focus on correctness bugs, leftover debug code, and anything I forgot to handle. List findings with file and line.

Agent

Two findings: session.ts:41 leaves a console.log of the token (remove it), and login.ts:18 returns before clearing the failed-attempt counter, so lockout never resets on success.

Scope the review to git diff --cached.

Step 3: Triage the findings

Go through each item and decide: fix now, defer, or dismiss as a false positive. Not every flag is real, so you stay the judge. The token log is a real leak; the lockout bug is worth fixing before commit.

Review findings

[ fix ] session.ts:41 console.log(token) -> remove, leaks secret

[ fix ] login.ts:18 early return skips counter reset

[ skip ] login.ts:22 style nit, not blocking

Step 4: Apply fixes and commit

Fix the real issues, re-stage, and commit. A clean self-review means your reviewer spends their time on design instead of catching a debug log.

git add src/auth/
git commit -m "Fix lockout reset and remove token debug log"

Review staged, not the whole tree

Using git diff --cached keeps Claude focused on what you are about to commit, so it does not get distracted by unrelated work in progress elsewhere in the tree.

Result: two real issues caught before the commit, a token no longer logged, and a cleaner change for whoever reviews the pull request.