Ehh that includes an API... Bottom line is I need the API version 3.0.0-ALPHA5 to code my Plugins ;-;
Do you know what an API is, or not? The PocketMine API is literally part of PocketMine. If you have the phar, you have the API.
Actually, an API is not necessary the exact source code or distribution of the software But you're right, just add the PocketMine repo as the library include path.
tell me if im wrong but source code is the program itself broken up into code while API is the library (or sdk like mentioned above) of the methods that is used by the program
I think where you are confused is that the 'program' here is the plugin (not PocketMine), and the API is the part of PocketMine that is exposed to plugins. People have already told you what you need: the PocketMine source code. The easiest way to get it is to git clone --recursive the PMMP github repo to get the latest source (currently at API 3.0.0-ALPHA5) and submodules, then add the src path to your IDE to get autocomplete etc.