# Reference

Lookup pages: the command surface, exit codes and gates, the skill catalogue, the page types. A
reference page describes what is, not how to use it or why it is so - and wherever a source for
it exists in the code, it is generated from that source and checked against it rather than
written by hand.

Nothing is generated here yet. Until it is, the command reference is
[tools/CONTRACT.md](../../tools/CONTRACT.md) (and `tools/wikitool <command> -h`), and a page
type is described by `tools/wikitool types describe <type>`.