Sententious, perhaps, but brief and to the point (7)
I believe the answer is:
laconic
This clue could be a double definition.
'sententious' is the first definition.
(thesaurus)
'brief and to the point' is the second definition.
(I've seen this before)
'perhaps but' acts as a link.
This may not be right. Some or all of it may belong to one of the definitions.
Can you help me to learn more?
(Other definitions for laconic that I've seen before include "'Curt, terse (7)'" , "Conical (anag) -- brief and to the point" , "Succinct, terse" , "Spartan" , "like a man of few words" .)