PR Reviewer Agent

The PR Reviewer agent is a specialized AI assistant for conducting thorough, constructive code reviews of .NET MAUI pull requests.

How to Use This Agent

• VS Code: Custom Agents in VS Code
• Copilot CLI: GitHub Copilot CLI

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What It Does

The PR Reviewer agent:

• ✅ Checks out the PR branch and analyzes the code changes
• ✅ Reviews test coverage - evaluates tests included in the PR
• ✅ Forms independent opinion - analyzes WHY the fix works (or doesn't)
• ✅ Identifies edge cases - finds scenarios that could break the fix
• ✅ Runs UI tests - validates the fix works on device/simulator
• ✅ Creates edge case tests - adds targeted tests for gaps identified during analysis
• ✅ Validates API changes - checks PublicAPI.Unshipped.txt correctness
• ✅ Writes comprehensive review - provides detailed feedback with test results

When to Use

Use the PR Reviewer agent when:

• You want a comprehensive code review with hands-on testing validation
• You need to verify a PR's fix actually works through UI testing
• You want to validate test coverage and code quality
• You want to identify and test edge cases not covered by the PR
• You're reviewing someone else's PR with thorough analysis

What makes this different: This agent doesn't just read code - it checks out the PR, runs the tests, adds edge case tests if needed, and validates the fix works.

Example Prompts

review PR #12345

review PR #12345 focusing on test coverage

review PR #12345 and check if the API changes are correct

review this PR

does PR #12345 have adequate test coverage?

review PR #12345 and PR #12346 - which approach is better for fixing issue #12000?

review my changes before I submit a PR

review PR #12345 - I'm concerned about thread safety in the Android handler

review PR #12345 and verify PublicAPI.Unshipped.txt is correct

What to Expect

When you invoke the PR Reviewer, it will:

1. Checkout PR branch - Fetches and switches to the PR code
2. Review code - Analyzes changes for correctness, performance, security
3. Review tests - Evaluates UI tests included in the PR
4. Deep analysis - Forms independent opinion on whether fix is correct
5. 🛑 Pause for approval - Presents analysis and waits for your confirmation
6. Run tests - Executes UI tests on device/simulator if you approve
7. Add edge case tests - Creates additional tests for gaps (if agreed)
8. Write review - Creates Review_Feedback_Issue_XXXXX.md with comprehensive findings

The review output includes:

• Recommendation: Approve / Request Changes / Comment
• Code Analysis: WHY the fix works (or concerns about it)
• Test Results: Which tests ran and what happened
• Edge Cases: What scenarios were validated beyond the basic fix
• Issues Found: Required fixes and recommended improvements

Tips for Best Results

Be Specific About Your Concerns

Instead of:

review PR #12345

Try:

review PR #12345 - I'm concerned about thread safety in the Android handler

Provide Context

review PR #12345 - this is a fix for a crash reported in issue #12000

Context helps the agent understand what to look for.

Ask Follow-up Questions

In your review of PR #12345, you mentioned potential memory leaks. Can you explain that concern in more detail?

The agent can elaborate on any point from its review.

Request Specific Checks

review PR #12345 and verify:
- PublicAPI.Unshipped.txt is correct
- All platforms are handled
- Error handling is comprehensive

What the PR Reviewer Does NOT Do

• ❌ Write comprehensive test suites - For that, use UI Test Coding Agent
  • This agent CAN create targeted edge case tests during validation
  • But won't write full test infrastructure or debug test frameworks
• ❌ Quick manual testing - For exploratory testing without deep analysis, use Sandbox Agent
  • This agent does thorough analysis before testing
  • Sandbox is better for "just try it out" scenarios

Common Use Cases

Before Submitting Your PR

review my changes before I submit a PR

Get feedback while you're still on your feature branch.

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Second Opinion

I got review feedback saying this approach is wrong. Can you review PR #12345 and suggest alternatives?

Get a different perspective on a contentious issue.

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Learning Best Practices

review PR #12345 and explain any MAUI-specific conventions I should know about

Learn repository patterns while getting your code reviewed.

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Validation Checklist

review PR #12345 and create a checklist of items I should address before requesting human review

Get an actionable todo list.

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