Claude doesn't generate any output from PR review

[Kraxi]

Describe the bug
After enabling the PR review done by Claude, it runs for several minutes and as a result from action there is no comment, nor report generated

To Reproduce
Steps to reproduce the behavior:

1. Enable default /install-github-app inside claude code's prompt
2. Merge the github actions content in a default form. Attaching the action below
3. Prepare a PR in your repo
4. Observer Claude performing review and not producing any output

Expected behavior
A PR comment with the review report

Screenshots

Workflow yml file

name: Claude Code Review

on:
  pull_request:
    types: [opened, synchronize, ready_for_review, reopened]
    # Optional: Only run on specific file changes
    # paths:
    #   - "src/**/*.ts"
    #   - "src/**/*.tsx"
    #   - "src/**/*.js"
    #   - "src/**/*.jsx"

jobs:
  claude-review:
    # Optional: Filter by PR author
    # if: |
    #   github.event.pull_request.user.login == 'external-contributor' ||
    #   github.event.pull_request.user.login == 'new-developer' ||
    #   github.event.pull_request.author_association == 'FIRST_TIME_CONTRIBUTOR'

    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: read
      issues: read
      id-token: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 1

      - name: Run Claude Code Review
        id: claude-review
        uses: anthropics/claude-code-action@v1
        with:
          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
          plugin_marketplaces: 'https://github.com/anthropics/claude-code.git'
          plugins: 'code-review@claude-code-plugins'
          prompt: '/code-review:code-review ${{ github.repository }}/pull/${{ github.event.pull_request.number }}'
          # See https://github.com/anthropics/claude-code-action/blob/main/docs/usage.md
          # or https://code.claude.com/docs/en/cli-reference for available options

API Provider

[X] Anthropic First-Party API (default)
[ ] AWS Bedrock
[ ] GCP Vertex

Additional context
Add any other context about the problem here.

[joejansen]

I have the same issue.

[Xavier-IV]

For now, i have to explicitly call "(at)claude review this" in the PR comment, then that'll work.

While waiting for this fix, we can use that comment section to call out
But honestly this needs to be fixed, feels like spending 2x for this alone.

[Kraxi]

Yeah @Xavier-IV , calling claude via comment works, but the point of automatic PR reviews is to not call the Claude every time 😄

[wesleyfranks]

I'm experiencing the same but now I'm having the SDK bug that is crashing the workflow before it even starts.

[arjunven]

Same issue here. After debugging the action logs I found two root causes:

1. pull-requests: read should be pull-requests: write

The workflow generated by /install-github-app has:

permissions:
  pull-requests: read

Posting a review comment requires write access. Without it, the action runs to completion (is_error: false, subtype: success) but silently fails to post anything. The official pr-review-comprehensive.yml example in this repo correctly uses pull-requests: write.

2. All gh CLI calls are permission-denied by Claude's tool policy

The code-review plugin fetches the PR diff by running gh api and gh pr diff. Without explicitly allowing these, Claude Code's default tool permission policy blocks them. In the logs this shows up as a permission_denials list with 7 consecutive denied Bash calls — Claude tries multiple fallback strategies, all blocked, then gives up.

Fix is to pass allowed_tools via claude_args:

claude_args: '--allowedTools "Bash(gh api*),Bash(gh pr*),Bash(git*)"'

Full fixed workflow:

jobs:
  claude-review:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write   # was: read
      issues: read
      id-token: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 1

      - name: Run Claude Code Review
        id: claude-review
        uses: anthropics/claude-code-action@v1
        with:
          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
          plugin_marketplaces: 'https://github.com/anthropics/claude-code.git'
          plugins: 'code-review@claude-code-plugins'
          prompt: '/code-review:code-review ${{ github.repository }}/pull/${{ github.event.pull_request.number }}'
          claude_args: '--allowedTools "Bash(gh api*),Bash(gh pr*),Bash(git*)"'

The pull-requests: read in the generated workflow is a bug in /install-github-app — it should emit write for any code review setup.

[arjunven]

Hmm looks like anthropics/claude-code#7710 is identical and closed without a resolution.

Update:
Even after fixing the write permissions I run into a number of denied permissions when the action tries to call the gh cli.

The more i'm reading https://github.com/anthropics/claude-code/tree/main/plugins/code-review it looks like this plugin is really meant to be installed on your local claude code instance and not really meant to be run via a github action.

I am feeling like the /install-github-app is broken and perhaps hallucinated that the code-review plugin can be run in a GHA?

Filed anthropics/claude-code#26227 as well