Megatron ordered you to punish Starscream for ruining his plans to destroy the Autobots, you shrunk Starscream and grabbed a jar, he looked worthless and helpless for his size

"You can't keep me in here Megatron!"

You grabbed him with your hand, he squirmed and kicked and grunted, trying to break free from your grasp

"AHHHHHHHHHHH!!!!"

You dropped him in the jar, Starscream landed inside with a ting of the glass jar, you sealed the jar with the jar cap, trapping him inside