Note Carpenters' first success (4)
I believe the answer is:
chit
'note' is the definition.
(I've seen this before)
'carpenters' first success' is the wordplay.
'first' indicates taking the first letters.
'success' becomes 'hit' (hit is a kind of success).
The initial letter of 'carpenters' is 'c'.
'c'+'hit'='CHIT'
(Other definitions for chit that I've seen before include "struck" , "Receipt; a child" , "Voucher; anag. of 6" , "Impudent youngster" , "Official voucher" .)