xash3d-fwgs/Documentation/extensions/steam-broker.md

Steam broker protocol

sb_connect <ip:port> <server's steam id> <secure> <challenge> - used for obtaining auth ticket during connection to GoldSrc server

sb_disconnect <ip:port> <challenge> - used for signaling broker about disconnecting from GoldSrc server

sb_gamedir <gamedir> - used for signaling broker about game startup and for announcing started mod, so broker could choose proper AppID for Steam API initialization

sb_terminate - used for signaling broker about game shutdown, ideally broker should be terminated too (and later restarted automatically and waiting for sb_gamedir message)