Writer, King, presented with fine folding blade (8)
I believe the answer is:
penknife
'folding blade' is the definition.
(type of small knife)
'writer king presented with fine' is the wordplay.
'writer' becomes 'pen' (something which writes).
'king' becomes 'K' (abbreviation for king in chess).
'presented with' indicates an anagram (letters presented in a new way).
'k' anagrammed with 'fine' makes 'knife'.
'pen'+'knife'='PENKNIFE'
(Other definitions for penknife that I've seen before include "A Swiss army one has several blades and many tools" , "whittling tool" , "Small pocket cutting tool" , "What may be used for carving" , "Small folding pocket blade" .)