Until a few years ago, there were basically two tools you could use to generate API documentation in PHP: phpDocumentor and Doxygen. [...] phpDocumentor is practically unsupported at this time (though a small group of developers is working on a new version), and Doxygen has never had PHP as its primary concern. As such, a number of new projects are starting to emerge as replacements.
He introduces DocBlox as one of these alternatives and points out where you can get the latest version (from one of many sources including github, PEAR or by just grabbing a release. He includes instructions on how to run the tool on your code, use it to identify missing docblock comments and how to use the class diagrams feature that gives a more visual sense of how things fit together. He also mentions changing the title of the output, using different templates and how it uses a local SQLite database to cache the parsed information about your code (making it simpler and faster to do updates in the future).