coderabbit-hello-world

What this skill does

# CodeRabbit Hello World

## Overview

Minimal working example demonstrating CodeRabbit AI code review. CodeRabbit reviews PRs automatically via a GitHub/GitLab App -- no SDK or API calls needed. You configure behavior through a `.coderabbit.yaml` file and interact via PR comments.

## Prerequisites

- CodeRabbit GitHub App installed (see `coderabbit-install-auth`)
- A repository with at least one branch

## Instructions

### Step 1: Create Minimal Configuration

```yaml
# .coderabbit.yaml (repository root)
language: "en-US"
reviews:
  profile: "assertive"
  high_level_summary: true
  auto_review:
    enabled: true
    drafts: false
chat:
  auto_reply: true
```

### Step 2: Add Path-Specific Instructions

```yaml
# .coderabbit.yaml - add review context for better feedback
reviews:
  profile: "assertive"
  high_level_summary: true
  auto_review:
    enabled: true
    drafts: false
  path_instructions:
    - path: "src/**/*.ts"
      instructions: "Check for proper TypeScript types. Flag any use of `any`."
    - path: "**/*.test.*"
      instructions: "Verify edge cases are covered. Check async handling."
chat:
  auto_reply: true
```

### Step 3: Create a PR to Trigger Review

```bash
set -euo pipefail
git checkout -b feat/hello-coderabbit

# Add the configuration file
cat > .coderabbit.yaml << 'YAML'
language: "en-US"
reviews:
  profile: "assertive"
  high_level_summary: true
  auto_review:
    enabled: true
    drafts: false
  path_instructions:
    - path: "src/**"
      instructions: "Check for proper error handling and input validation."
chat:
  auto_reply: true
YAML

git add .coderabbit.yaml
git commit -m "feat: add CodeRabbit AI code review configuration"
git push -u origin feat/hello-coderabbit
gh pr create --title "feat: enable CodeRabbit AI code review" \
  --body "Adding .coderabbit.yaml for automated code reviews"
```

### Step 4: Interact with CodeRabbit on the PR

Once CodeRabbit posts its review (typically 2-5 minutes), you can interact:

```markdown
# In a PR comment, use these commands:
@coderabbitai summary        # Get a walkthrough of all changes
@coderabbitai full review    # Re-run a complete review from scratch
@coderabbitai resolve        # Mark all CodeRabbit comments as resolved
@coderabbitai help           # List all available commands

# Reply to any CodeRabbit comment to have a conversation about the feedback
# CodeRabbit will respond with context-aware explanations
```

### Step 5: Try the CLI for Local Reviews (Optional)

```bash
set -euo pipefail
# Review staged changes before committing
git add -A
cr review

# Review with interactive mode for back-and-forth discussion
cr review --interactive

# Review specific files
cr review src/index.ts src/utils.ts
```

## What CodeRabbit Posts on Your PR

1. **Walkthrough comment**: High-level summary of all changes with a file-by-file breakdown
2. **Sequence diagram**: Visual control flow of the changes (if enabled)
3. **Line-level comments**: Specific suggestions on individual code lines
4. **Review status**: Approved or changes-requested based on severity of findings

## Output

- `.coderabbit.yaml` committed to repository root
- First AI review posted on a test PR within 2-5 minutes
- Interactive review conversation demonstrated

## Error Handling

| Issue | Cause | Solution |
|-------|-------|----------|
| No review appears | App not installed on this repo | Check GitHub App > Repository access |
| YAML syntax error | Invalid configuration | Validate YAML at yamlchecker.com |
| Review on wrong branch | Missing base_branches filter | Add `base_branches: [main]` to config |
| Bot not responding to commands | Typo in mention | Must use exact `@coderabbitai` mention |

## Resources

- [YAML Configuration Guide](https://docs.coderabbit.ai/getting-started/yaml-configuration)
- [Review Commands Reference](https://docs.coderabbit.ai/reference/review-commands)
- [CodeRabbit CLI](https://www.coderabbit.ai/cli)

## Next Steps

Proceed to `coderabbit-local-dev-loop` for a full development workflow with CodeRabbit.