GitHub PR Review with Claude Code

This guide explains how to have Claude Code review GitHub Pull Requests and post review comments directly to the PR.

Prerequisites

1. GitHub CLI (gh)

The GitHub CLI is required for Claude Code to interact with GitHub PRs.

Installation:

# macOS
brew install gh

# Ubuntu/Debian
sudo apt install gh

# Windows
winget install GitHub.cli

Verify installation:

gh --version

2. GitHub Authentication

Authenticate the GitHub CLI with your account:

gh auth login

Follow the prompts to authenticate via browser or token.

3. GitHub Token Permissions

When authenticating, the token needs specific scopes to review PRs:

Scope	Purpose	Required
repo	Full access to private repositories	Yes (for private repos)
public_repo	Access to public repositories only	Yes (for public repos only)
write:discussion	Create/edit PR comments and reviews	Yes

For fine-grained tokens (recommended):

Permission	Access Level	Purpose
Pull requests	Read and write	View PR details, post reviews
Contents	Read	Read PR diff and changed files
Metadata	Read	Repository metadata

Check current authentication:

gh auth status

Refresh authentication with required scopes:

gh auth refresh -s repo,write:discussion

Reviewing a PR

Method 1: Direct Review Command

Ask Claude Code to review a PR by number or URL:

Review PR #123 and post a code review comment

or

Review https://github.com/owner/repo/pull/123 and comment on it

Method 2: Step-by-Step

1. View PR details:

gh pr view 123 --json title,body,author,files,commits

1. View the diff:

gh pr diff 123

1. Post a review:

gh pr review 123 --approve --body "LGTM! Code looks good."

or with comments:

gh pr review 123 --comment --body "Review comments here..."

or request changes:

gh pr review 123 --request-changes --body "Changes needed..."

Review Actions

Action	Command	Description
Approve	gh pr review N --approve	Approve the PR
Comment	gh pr review N --comment	Add review without approval
Request Changes	gh pr review N --request-changes	Request modifications
Add Line Comment	gh api (see below)	Comment on specific lines

Adding Line-Level Comments

For inline comments on specific lines:

gh api repos/{owner}/{repo}/pulls/{pr}/comments \
  -f body="Comment text" \
  -f commit_id="SHA" \
  -f path="path/to/file.go" \
  -F line=42 \
  -f side="RIGHT"

Example Review Workflow

When you ask Claude Code to review a PR, it will:

1. Fetch PR metadata — Title, description, author, branch info
2. Fetch the diff — All changed files and their modifications
3. Analyze changes — Security issues, code quality, best practices
4. Generate review — Summary with specific findings
5. Post review — Submit the review to GitHub

Troubleshooting

"Resource not accessible by integration"

Your token lacks required permissions. Re-authenticate:

gh auth refresh -s repo,write:discussion

"Must have admin rights to Repository"

For organization repos, ensure:

• You have write access to the repository
• Organization allows third-party access (if using OAuth app)

"Not Found" Error

• Verify the PR number/URL is correct
• Check you have access to the repository
• For private repos, ensure repo scope is granted

Security Considerations

• Claude Code only reads PR content for review purposes
• Review comments are posted under your GitHub identity
• Tokens are stored locally by the gh CLI
• Never share tokens or authenticate Claude Code with admin-level tokens

Related Commands

# List open PRs
gh pr list

# Check out a PR locally
gh pr checkout 123

# View PR checks/status
gh pr checks 123

# Merge a PR (after approval)
gh pr merge 123