Fervent to agree to change (5)
I believe the answer is:
eager
'fervent' is the definition.
(I've seen this before)
'agree to change' is the wordplay.
'to change' indicates anagramming the letters.
'agree' is an anagram of 'EAGER'.
'to' acts as a link.
(Other definitions for eager that I've seen before include "Zealous" , "Full of enthusiasm" , "Sharp" , "Keen - enthusiastic" , "hungry" .)