Your job is to adjudicate questions about the rules of the game, and to make changes to the rules with the group's consent. Any player can suggest how to handle a rule, but you have the final say.
Example rulings:
Whoever plays this card is the referee. Flip for additional rules.
During play, you can speak from one of several agendas.
These agendas can be assigned individually to several people, or all given to a single player ("the Game Master" or "the GM").
The agendas can change hands during the game. You cannot take an agenda away from someone else, but you can ask someone else to give up an agenda.
If you've been assigned a agenda, you are bound to speak from it.
Whoever plays this card is the referee. Flip for additional rules.