At outset positive, look up manager’s description of well-paid job (4)
I believe the answer is:
plum
'description of well-paid job' is the definition.
'at outset positive look up manager's' is the wordplay.
'at outset' indicates taking the first letters.
The initial letters of 'positive look up managers' is 'PLUM'.
(Other definitions for plum that I've seen before include "Shade" , "Prize" , "Fruit; something choice" , "Purple fruit" , "Dark-red fruit" .)