They do have a headset and can talk to their guy with the mic on the field. They are responsible for coaches challenges (throwing the red flag). They accept or

They do have a headset and can talk to their guy with the mic on the field. They are responsible for coaches challenges (throwing the red flag). They accept or decline penalties against the opponent. and obviously the buck stops with them in terms of the decision making of the coordinators/play callers. But certainly a lot of the work is the prep.