Review, and Claude in your pull requests

The work that most needs a second reader is the work nobody watched. There are two ways to get one, and they are not the same product.

Code Review reads the change in the context of the whole codebase rather than the diff alone, which is the part a human reviewer usually skips. Findings do not approve or block the pull request, so it slots in beside whatever review process already exists.

You steer what it flags with a CLAUDE.md or a REVIEW.md in the repository. That is the same file from lesson 10 doing a second job: the conventions you wrote for the session are the conventions the review holds you to.

The action, in one file

name: Claude
on:
  issue_comment:
    types: [created]

jobs:
  claude:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: anthropics/claude-code-action@v1
        with:
          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}

With that in place, mentioning @claude in a pull request or an issue starts a run in your own CI, with your repository checked out. It is the headless mode from the last lesson with GitHub events as the trigger.