Details put as specified in the agreement (10)
I believe the answer is:
stipulated
'details put as specified in the agreement' is the definition.
I can't tell whether this defines the answer.
'details put as specified in' is the wordplay.
'details put as' becomes 'tipu' (I can't justify this - if you can you should believe this answer much more).
'specified' becomes 'slated' (slating is a kind of specifying).
'in' indicates putting letters inside.
'tipu' inserted into 'slated' is 'STIPULATED'.
Can you help me to learn more?
(Another definition for stipulated that I've seen is " Required, specified".)