Exactly what’s needed (4,3,3)
I believe the answer is:
just the job
'exactly what's needed' is the definition.
(just the job means the very thing needed)
This is all the clue.
(Other definitions for just the job that I've seen before include "The position is all" , "Exactly what was required" , "The very thing" , "fine!" , "Exact requirement" .)