apiato : apiato is a starter project, designed to help you build scalable API’s faster, by providing tools and functionalities that facilitates the development...
ApiGen : ApiGen is the tool for creating professional API documentation from PHP source code, similar to discontinued phpDocumentor/phpDoc.
htty : htty is a console application for interacting with web servers. It’s a fun way to explore web APIs and to learn the ins and outs of HTTP.
YOURLS stands for Your Own URL Shortener. It is a small set of PHP scripts that will allow you to run your own URL shortening service (a la TinyURL or bitly).