The LA Grind has the (true) answer. For example:
Assistant DirectorStop banging your head on the desk, Johnnie. It is funny.
Implied Position & Responsibilities: Create schedules, keep crew and director on schedule for the day, contacting late crew members, sending out tomorrow’s schedule.
Actual Low Budget Requirements/Expectations: Assist the director by getting coffee, dry cleaning, picking up food for the rest of the crew.