/HELP [command|+topic]

Display some help about a command or a topic.
If no argument provided a usage of this command is printed.
Available commands: add, alias, authorization, bind, buffer, chat_disable, clear, color, connect, del, disconnect, echo, event, group, help, iline, info, module, move, msay, otr, otrpolicy, pgp, quit, rawxml, rename, request, room, roster, say_to, say, screen_refresh, set, source, status_to, status, version.