Rest should contribute half of table tip servers raised (7)
I believe the answer is:
respite
'rest' is the definition.
(synonyms)
'should contribute half of table tip servers raised' is the wordplay.
'should contribute half of' indicates a hidden word (half of the letters in that part of the clue).
'raised' is a reversal indicator.
'etipser' is hidden in the letters of 'table tip servers'.
'etipser' back-to-front is 'RESPITE'.
(Other definitions for respite that I've seen before include "Pause from exertion, etc" , "Short break" , "Period of temporary relief" , "Short let-up" , "Short period of rest" .)