Ralph Schindler gives an overview of extending the Zend Framework tool Zend_Tool. He describes Zend_Tool's purpose for rapid application development of Zend Framework projects. The talk outlines Zend_Tool's architecture including the Zend_Tool_Framework component for dispatching tool requests and the Zend_Tool_Project component for exposing project-specific capabilities. Schindler discusses various extension points for Zend_Tool like implementing providers, metadata, and interactivity. He provides examples of extending Zend_Tool to load profiles, create resources, and regenerate code.