Value tip of writer (5)
I believe the answer is:
point
I believe this is a double definition.
'value' is the first definition.
(thesaurus)
'tip of writer' is the second definition.
(tip of a pen - something that writes)
(Other definitions for point that I've seen before include "Any of thirty-two directions" , "Sharp or tapering end" , "Fielder" , "The whole idea" , "Crux" .)