Agent receives a fixed share of compensation (10)
I believe the answer is:
reparation
'compensation' is the definition.
(I know that reparation is a type of compensation)
'agent receives a fixed share' is the wordplay.
'agent' becomes 'rep' (short for representative).
'receives' becomes 'a' (I can't explain this - if you can you should give a lot more credence to this answer).
'a fixed share' becomes 'ration' (I've seen this before).
'rep'+'a'+'ration'='REPARATION'
'of' is the link.
Can you help me to learn more?
(Other definitions for reparation that I've seen before include "The making of amends for a wrong" , "process of putting things right again" , "make redress" , "compensation" , "damages" .)