Advise on clues to be rewritten (7)
I believe the answer is:
counsel
'advise' is the definition.
('counsel' can be a synonym of 'advise')
'on clues to be rewritten' is the wordplay.
'to be rewritten' indicates an anagram (I've seen 'being rewritten' mean this).
'on'+'clues'='onclues'
'onclues' with letters rearranged gives 'COUNSEL'.
(Other definitions for counsel that I've seen before include "kept by the secretive" , "kept by the uncommunicative" , "Legal adviser" , "Lawyer who pleads cases in court" , "Recommend - barrister" .)