Good-natured dope you heard is in love (8)
I believe the answer is:
generous
'good-natured' is the definition.
(thesaurus)
'dope you heard is in love' is the wordplay.
'dope' becomes 'gen' (both can mean information).
'you heard' becomes 'U' (homophone of 'you').
'is in' means one lot of letters goes inside another.
'love' becomes 'eros' (Greek god of love).
'u' placed within 'eros' is 'erous'.
'gen'+'erous'='GENEROUS'
(Other definitions for generous that I've seen before include "Charitable" , "Benevolent, big-hearted" , "Kind towards others" , "Showing largess" , "Free" .)