This is probably a nobrainer for a lot of people, but given my limited knowledge of Python I found this useful to write. Load the script and issue /inspect to see all the public methods of the xchat object.

# -*- coding: utf-8 -*-

__module_name__ = "XChat Inspect"
__module_version__ = "0.1.20100130"
__module_description__ = "Print the interface of the xchat object"

import xchat

def inspect(word, word_eol, userdata):
    methods = xchat.__dict__
    for key in methods:
        print chr(2), key, chr(2), methods[key]
    return xchat.EAT_NONE

xchat.hook_command("inspect", inspect)