The ClientTick Event is fired every tick on the client.

You will need to cast the event in the function header as this class:
crafttweaker.event.ClientTickEvent
You can, of course, also import the class before and use that name then.

WorldTick Events implement the following interfaces and are able to call all of their methods/getters/setters as well:

• ITickEvent

There is no additional information besides the information mentioned in the interfaces above.