Communicate the writer's role (6)
I believe the answer is:
impart
'communicate' is the definition.
(imparting is a kind of communicating)
'the writer's role' is the wordplay.
'the writer's' becomes 'im' (both could mean 'the crossword setter is').
'role' becomes 'part' ('part' can be a synonym of 'role').
'im'+'part'='IMPART'
(Other definitions for impart that I've seen before include "Share, pass on" , "Give, say information, make known" , "Reveal about armpit" , "grant" , "Communicate (info)" .)