Plotscript arguments passed by CUSTOM

I've looked around on the wiki, and can't find anything. What arguments are passed to scripts that are called from various game stuff?

For example, I know that "instead of battle" passes a formation number. Do NPCs that call scripts pass a reference the NPC? A list of similar things would be nice, and would probably save quite a bit of time. And would free up the argument passing field when we have a script that, for example, functions on every NPC in the game world. Although there are other ways to get around that...

But anyway, yeah.

There is an article on the wiki:

http://gilgamesh.hamsterrepublic.com/wiki/ohrrpgce/index.php?title=Script_triggers