Signs with certain pieces of text should have the effect of executing a command, to help reduce the number of commands players are forced to type. Restrict usage of signs to be before a match has started and only in the spawn area, to limit the ways it can be abused. I propose the following format:

• Line 1 should always be [AutoReferee]
• Line 2 should be the action (maybe jointeam Red)
• Line 3 should be additional arguments
• Line 4 is ignored and can be custom text

For jointeam signs, it was suggested to maybe attempt to implement colored signs.