Agree officer has right to reply (10)
I believe the answer is:
correspond
'agree' is the definition.
(I know that agree can be written as correspond)
'officer has right to reply' is the wordplay.
'officer' becomes 'co' (Commanding Officer abbreviation).
'has' is a charade indicator (letters next to each other).
'right' becomes 'r' (common abbreviation).
'to reply' becomes 'respond' ('respond' can be a synonym of 'reply').
'co'+'r'+'respond'='CORRESPOND'
(Other definitions for correspond that I've seen before include "Communicate by letter" , "Communicate; agree" , "Keep in touch by letter" , "Write - match" , "answer" .)