Well the Phex API is probably not as simple as you would wish it to be, but we are currently in the process to make the API more easier to use.
Also there is not really much documentation available for Phex. We have a very small team and all we can offer is JavaDoc API documentation.
http://www.phex.org/javadoc/phex/
Basically everything (or almost everything until its refactored) is based around the class phex.servent.Servent

Check out the source of phex.Main to see how to initialize the Servent and then you can use the Servent API to navigate through the modules like network, search, download and shared files.

If you are looking for anything specific drop us a note and we will do our best to assists you or improve things in the API.

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