Graphite Reviewer is an AI-powered code review tool that enhances team efficiency and quality in code reviews through instant feedback. The tool utilizes a codebase-aware AI to automatically detect bugs and errors, allowing teams to focus on building rather than reviewing. It supports custom rules to ensure code quality and consistency while maintaining the privacy and security of the code. Key benefits of Graphite Reviewer include rapid PR merges, enhanced quality and consistency, code privacy and security, and capturing common errors.