The kind to work as a key operative (4)
I believe the answer is:
type
'the kind' is the definition.
(type is a kind of kind)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for type that I've seen before include "Sort, kind" , "Write using a keyboard" , "Print form" , "Use a keyboard; sort" , "Mark" .)