Setting Up Claude Code for AI-Powered PR Reviews in GitHub

Setting Up Claude Code for AI-Powered PR Reviews in GitHub

There is a major shift happening in software delivery right now.

Developers are no longer just using AI to write code locally. We are moving into the next layer: using AI to improve the entire pull request process.

That means AI can help review PRs, explain changes, find missing tests, identify risk, and help human reviewers move faster with better evidence.

But there is one important thing teams need to understand:

You cannot just type @claude review in a GitHub pull request and expect it to work automatically.

The repository must first be connected to Claude Code.

The good news is that Anthropic has made this setup much easier. For direct Anthropic API users, the recommended quick setup is done from the command line inside Claude Code.

The command is:

/install-github-app

That command walks you through installing the Claude GitHub App and setting up the required GitHub secrets for the repository. Anthropic’s Claude Code GitHub Actions documentation describes this as the easiest setup path for GitHub integration.

Once that is done, the team can use comments like this inside a pull request:

@claude review this PR

or better:

@claude review this PR against the story, intent file, CLAUDE.md, repo architecture, tests, security, and data/API contract risk. Return only material findings and rank them High, Medium, or Low.

That is when Claude becomes part of the PR review workflow.

Not before.

What This Actually Sets Up

When you run the Claude Code GitHub setup, you are connecting the repository to Claude’s GitHub automation layer.

At a high level, this gives the repo the ability to respond to Claude mentions in GitHub issues and pull requests.

The flow looks like this:

Developer or reviewer comments: @claude review

        ↓

GitHub detects the comment

        ↓

Claude GitHub integration / GitHub Action runs

        ↓

Claude reads the pull request context

        ↓

Claude reviews the code, diff, and repo instructions

        ↓

Claude posts comments back into the PR

The comment is the trigger.

The GitHub App and GitHub Action are the engine.

Without the setup, @claude review is just a normal GitHub comment.

The Command-Line Setup

The simplest path is:

cd your-repo

claude

/install-github-app

From there, Claude Code guides you through the GitHub setup process.

This typically includes:

Installing the Claude GitHub App

Authorizing the repository

Adding required GitHub secrets

Creating or updating the GitHub Actions workflow

Granting permissions for PR and issue interaction

You usually need repository admin access because installing a GitHub App and adding repository secrets are administrative operations.

This is important for enterprise teams. A normal developer may be able to use Claude Code locally, but they may not have permission to install the GitHub App for the repo. In that case, a repo admin, platform engineer, or DevOps owner needs to perform the setup.

What Happens After Setup

Once the repository is connected, the developer or reviewer can manually call Claude from inside a PR.

For example, the reviewer opens the pull request and types this in the PR comment box:

@claude review

Then click Comment.

Claude will start reviewing the PR based on the workflow configuration.

A better team-standard command would be:

@claude review this PR against the story, intent file, CLAUDE.md, repo architecture, tests, security, and data/API contract risk. Return only material findings. Rank each finding as High, Medium, or Low. Include what the human reviewer should verify before approval.

That is the kind of prompt that makes the review useful.

We do not want Claude to nitpick spacing.

We want Claude to help us find risk.

Where the Output Appears

Claude’s output appears inside GitHub.

Depending on the setup, output may show up in a few places:

PR conversation comments

Inline review comments on changed files

GitHub Actions run logs

GitHub Checks status

Summary comments in the pull request

This is the key advantage.

The team does not need to leave the PR.

The AI review lives where the human review already happens.

What Claude Can Review

Claude can help inspect the PR through multiple lenses:

Does this satisfy the story?

Does this match the intent file?

Does it follow CLAUDE.md?

Does it follow the repo architecture?

Are tests missing?

Are tests shallow?

Are there security risks?

Are there API contract risks?

Are there database or migration risks?

Is the PR too large?

Are there out-of-scope changes?

This is where AI becomes much more than a code generator.

It becomes a review partner.

The Role of CLAUDE.md

Every serious repo should have a CLAUDE.md file.

This file tells Claude how the repository works.

It should include:

Repo purpose

Architecture rules

Coding standards

Testing commands

Security expectations

PR rules

Things not to do

Build commands

Run commands

Example:

# CLAUDE.md

## Repo Purpose

This service handles provider onboarding and data validation.

## Architecture Rules

Controllers should stay thin.

Business logic belongs in services.

Data access belongs in repositories.

Do not bypass validation services.

## Testing

Run unit tests before opening a PR.

Add tests for new business rules.

Add integration tests for API behavior changes.

## Security

Do not log PII.

Do not hardcode secrets.

Do not bypass authorization checks.

## PR Rules

Keep PRs small.

Link the Jira story.

Include test evidence.

Document migration or API contract changes.

Without CLAUDE.md, Claude has to infer too much.

With CLAUDE.md, Claude can review against the team’s real standards.

This is one of the most important parts of getting value from Claude Code at the team level.

The Standard Manual PR Review Command

For teams just getting started, I would standardize one comment.

Use this:

@claude review this PR against the story, intent file, CLAUDE.md, repo architecture, tests, security, and data/API contract risk. Return only material findings. Rank each finding as High, Medium, or Low. Include what the human reviewer should verify before approval.

That gives Claude a clear job.

It also teaches developers what matters:

Intent

Architecture

Tests

Security

Data/API risk

Human approval

That is exactly the behavior we want to reinforce.

Manual First, Automatic Later

Do not start by automating everything.

Start manually.

Phase one should be simple:

Developer builds locally with Claude Code

Developer opens PR

Pipeline runs build and tests

Reviewer comments @claude review

Claude reviews the PR

Human reviewer makes the final decision

This keeps the process safe.

Once the team understands the output, then you can automate more.

Later, you can trigger Claude automatically when PRs touch risky areas like:

Authentication

Authorization

Database migrations

API contracts

Infrastructure

Secrets/configuration

PII or sensitive data

Payment or financial logic

That is the right progression.

Manual first.

Targeted automation second.

Full automation only after the team trusts the process.

What This Means for Developers

Developers should not think of Claude PR review as a punishment.

It is not there to embarrass them.

It is there to help them submit better PRs.

Before opening a PR, the developer should already use Claude Code locally:

Review my branch before I open a PR.

Check the story, intent file, CLAUDE.md, tests, architecture, and risk.

Give me the issues I should fix before asking for human review.

That should happen before the team sees the PR.

Then the GitHub-level @claude review becomes the second review layer.

The developer improves the PR locally.

The pipeline validates it.

Claude reviews it in GitHub.

The human reviewer approves it.

That is the new standard.

What This Means for Reviewers

The reviewer is still the decision-maker.

Claude does not approve the PR.

Claude does not own the merge.

The human reviewer owns the decision.

But now the reviewer has better evidence.

Instead of reading a PR cold, the reviewer can see:

What changed

What Claude found

What tests ran

What risks exist

What needs human verification

That makes reviews faster and better.

The reviewer’s job becomes:

Validate the intent

Validate the architecture

Validate the tests

Validate the risks

Approve only when the evidence is clean

This is how we make PR review more disciplined without slowing the team down.

The Best Team Standard

Here is the operating model I would recommend for every repo:

1. Add CLAUDE.md

2. Add a PR template

3. Add required CI checks

4. Install Claude GitHub integration

5. Start with manual @claude review

6. Require human approval

7. Track findings and defects

8. Automate risky-path reviews later

That is practical.

That is safe.

That is how teams move from “we use AI to write code” to “we use AI to improve software delivery.”

Final Thought

The goal is not to let AI take over PR review.

The goal is to make every PR arrive cleaner, smaller, better tested, better explained, and easier for a human to approve.

Claude Code gives us the local development assistant.

GitHub Actions gives us the automation layer.

@claude review gives us the AI reviewer inside the pull request.

The human reviewer still makes the final call.

That is the right balance.

AI assists.

Automation validates.

Humans decide.

:::

A note for accuracy when you post it: the setup is Claude Code, and the command is /install-github-app. Anthropic’s docs say it guides setup of the GitHub app and required secrets, and that repo admin access is needed.