Syntax
Description
The review command runs Codex in code review mode. You can review uncommitted changes, compare against a base branch, review a specific commit, or provide custom review instructions.
The review command runs non-interactively like codex exec. Use codex review --help for all available options.
Usage
Review Uncommitted Changes
codex review --uncommitted
Review Against Base Branch
Compare current branch with main:
codex review --base main
codex review --base develop
Review Specific Commit
codex review --commit abc123
codex review --commit HEAD~1
codex review --commit abc123 --commit-title "Add user authentication"
Custom Review Instructions
Provide specific review criteria:
codex review "focus on security vulnerabilities"
codex review "check for performance issues"
codex review "ensure code follows project style guide"
echo "review for accessibility issues" | codex review
codex review < review-checklist.txt
Options
Review Target
Review uncommitted changes in the working directory.
Review changes compared to a base branch (e.g., main, develop).
Review a specific commit by SHA or reference (e.g., abc123, HEAD~1).
Provide a commit title for context. Only valid with --commit.
Custom review instructions. Use - to read from stdin.
Output
-o, --output-last-message
Save the review report to a file.
Output review events as JSON Lines.
Model & Execution
AI model to use for the review.
Control colored output: auto, always, never.
Examples
Pre-Commit Review
# Review before committing
codex review --uncommitted
# Save review to file
codex review --uncommitted -o pre-commit-review.md
Pull Request Review
# Review changes in current branch vs main
codex review --base main
# Review with JSON output for CI
codex review --base main --json > pr-review.jsonl
Commit Review
# Review the last commit
codex review --commit HEAD
# Review a specific commit with context
codex review --commit abc123 --commit-title "Fix authentication bug"
# Review a range of commits
for commit in $(git log --format=%H -n 5); do
codex review --commit $commit -o "review-$commit.md"
done
Focused Reviews
# Security review
codex review --uncommitted "focus on security vulnerabilities and input validation"
# Performance review
codex review --base main "identify performance bottlenecks and optimization opportunities"
# Code quality review
codex review <<EOF
Review for:
- Code duplication
- Proper error handling
- Test coverage
- Documentation completeness
EOF
CI/CD Integration
# GitHub Actions
name: Code Review
on: [pull_request]
jobs:
review:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
with:
fetch-depth: 0 # Full history for base comparison
- name: Review Changes
run: |
codex review --base ${{ github.base_ref }} --json > review.jsonl
codex review --base ${{ github.base_ref }} -o review-report.md
- name: Upload Review
uses: actions/upload-artifact@v3
with:
name: code-review
path: review-report.md
Pre-Commit Hook
#!/bin/bash
# .git/hooks/pre-commit
echo "Running Codex review on uncommitted changes..."
codex review --uncommitted -o /tmp/codex-review.txt
if [ $? -ne 0 ]; then
echo "Review failed. See /tmp/codex-review.txt for details."
exit 1
fi
echo "Review complete. See /tmp/codex-review.txt"
Different Models
# Use GPT-4.1 for thorough reviews
codex review --base main -m gpt-4.1
# Quick review with o4-mini
codex review --uncommitted -m o4-mini
Review Output
By default, Codex outputs the review to stderr. Use -o to save to a file:
codex review --uncommitted -o review.md
--json, events are emitted as JSON Lines:
codex review --base main --json | jq -r 'select(.msg.type=="text") | .msg.content'
Exit Codes
0 - Review completed successfully1 - Error occurred during review
The exit code indicates whether the review ran successfully, not whether the code passed review. Check the review content for findings.