pax brief - legal requirement (belts, doors, evacuation, jackets, phones, etc).
captain's brief - not a legal requirement.
if you do wish to give one then if something is standard do not amplify. ie standard take off, standard efato drills, crosswind from the right. if it is non standard then comment on the differences. ie short field take off with 25 degrees flap, rotate speed 50kts, retract flaps at 200' and adjust to standard climb, standard efato drills except we will have flaps below 200', crosswind from the right.
something along those lines - short and sweet.