On most networks, you can use /stats m to get a list of all the raw commands (but not their syntaxes). You have to keep in mind, though, that not all of those commands are for users; some are for IRC operators and some are even server-to-server only, or for use by services only.
For bahamut, I wrote up a file that contains the syntaxes for all 48 of the commands available (at the time - there are more now, though I don't think there are any more user commands). It's available
here.
