Pitbull dressed in a Men In Black uniform for his music video.
Agent A is the name that rapper, songwriter and record producer Pitbull calls himself in his music video for his song "Back In Time", which he produced for Men in Black 3. The "A" stands for Armando, his legal first name.
In the music video, he is shown to be in the Chinese restaurant at the same time as Agent J, which means he was probably assisting him in his investigation of the restaurant. He follows a girl named Barbara Alba, who seems to be a fellow agent, around, who kills an alien at the restaurant. They return to base and he travels back in time. However, upon travelling back in time, he seems to have taken a break, as he is seen dancing at a nightclub.