The KGS Go Server only permits ranked games on 19×19 boards, but does allow bots (Go engines) to compete against other humans as well as other bots. However, you must create an account to play on the KGS server and must further obtain special permission to run a bot in ranked matches (although unranked, “free” games are allowed by default).
To connect a GTP Go Engine to KGS you must use the official kgsGTP client. If the engine attempts to join an automatch ranked game but is logging in with an account that does not have permission to do so you will receive the following error from the server:
FINE: Auth level is not ROBOT_RANKED, can only play free games
This means you must get permission from the KGS admins for a dedicated ranked bot account (firstname.lastname@example.org, the documentation stating email@example.com appears to be outdated).
The very first time running your bot as a ranked bot, you may receive the error:
java.lang.IllegalStateException: In automatch mode with no rank, you must provide the "automatch.rank" option
This is relatively straightforward, but to further clarify it means in the configuration file given to kgsGTP.jar you must add a default “guess” rank such as”
A more detailed tutorial using GNUGo: http://michna.com/kgsbot.htm