Agent — with assistance — settled debts (6)
I believe the answer is:
repaid
'settled debts' is the definition.
'repaid' can be an answer for 'settled' (I've seen this in another clue). I'm not certain of the 'debts' bit.
'agent with assistance' is the wordplay.
'agent' becomes 'rep' (short for representative).
'with' says to put letters next to each other.
'assistance' becomes 'aid' (synonyms).
'rep'+'aid'='REPAID'
Can you help me to learn more?
(Other definitions for repaid that I've seen before include "Diaper (anag.)" , "Returned" , "Compensated" , "Recompensed" , "no longer outstanding" .)