Claude GitHub App: Code Review always reports 0 issues, @claude mentions get no response

Description

We have the Claude GitHub App installed on our GitHub org with Code Review enabled. The integration appears partially functional — check runs are created — but Code Review never finds any issues and @claude mentions on PRs get no response.

This has been the case across ~8 PRs over the past few weeks.

Setup

• Claude GitHub App: Installed 3 weeks ago
• Permissions: Read access to actions/metadata, read+write access to checks, code, discussions, issues, PRs, and workflows
• Repository access: 6 selected repositories
• Code Review: Enabled (toggle on), set to "After every push" for the affected repo
• Avg Cost column shows $0.00 for the repo in question

Reproduction

1. Created a test PR (auction-mobile#761) with intentionally buggy code including:

• Hardcoded API keys (sk_live_...) and database credentials
• eval() usage
• Memory leaks (missing useEffect cleanup)
• Off-by-one errors (i <= array.length)
• == instead of ===
• Unchecked JSON.parse() on nullable values
• Missing key props in React list rendering
• Blocking synchronous sleep() with while loop
• Passwords stored in AsyncStorage
• API keys passed in URL query strings
• No error handling on fetch calls

1. The Claude Code Review check run completed in ~36s with:

``json
{
"conclusion": "neutral",
"output": {
"summary": "No high-confidence issues detected in this change.",
"title": "Code review found no issues",
"annotations_count": 0
}
}
``

1. Commented @claude review this PR on the PR — no response at all.

What we expected

At minimum, hardcoded secrets and eval() should be flagged. And @claude mentions should get a response.

What we've verified

• App is installed with correct permissions (screenshot confirmed)
• Code Review is toggled on and set to "After every push"
• The repo is in the selected repositories list
• The check run IS being created (so GitHub → Anthropic communication works at some level)
• This is consistent across ~8 real PRs, not just the test PR

Questions

• Is $0.00 avg cost expected, or does it indicate the review isn't actually running?
• Is there an org-level configuration step we might be missing?
• Are webhook deliveries from GitHub reaching Anthropic's servers? (The check run appearing suggests yes, but @claude not responding suggests maybe not for all event types)

Environment

• GitHub org plan: Team
• Anthropic plan: Claude Pro (with Teams features)
• Affected repo: React Native / Expo mobile app (TypeScript)

Related issues

• #33206 — Code Review finds issues but posts zero comments
• #26227 — /install-github-app generates broken workflow