No, the WebSockets are not officially supported. They are internal to Stack Exchange, use them at your own risk.
If it is at all possible to do your task with the API, use that. That's what it's there for.
Some people have sussed out **some of the endpoints**. You can see them in the answers to: [**How do the Stack Exchange WebSockets work? What are all the options you can send to them?**][4]
There was some talk of open-sourcing Stack Exchange's custom protocol (not the endpoints):
Note by Marc Gravell♦: if people would be genuinely interested in our releasing this as open source, please let us know. It will take some effort. but isn't impossible.
But this doesn't seem to have happened.
