Hotel worker is nice to pert model (12)
I believe the answer is:
receptionist
'hotel worker' is the definition.
(hotels often employ receptionists)
'is nice to pert model' is the wordplay.
'model' indicates an anagram.
'is'+'nice'+'to'+'pert'='isnicetopert'
'isnicetopert' anagrammed gives 'RECEPTIONIST'.
(Other definitions for receptionist that I've seen before include "Front desk worker" , "Front-desk worker" , "One greeting visitors" , "Hotel worker" , "One taking care of callers" .)