The document discusses various PHP static analysis tools and documentation generators that help maintain code quality in large projects. Key tools include PHP CodeSniffer, PHP Mess Detector, PHP Depend, and PHP Copy/Paste Detector, each serving different purposes like enforcing coding standards, detecting potential bugs, and measuring code quality metrics. Other tools mentioned include PHP Metrics, PHP-CS-Fixer, and documentation generators like PHPDox and PHPDocumentor, which assist in producing and improving project documentation.