Agile, fit to be frisky in New York (5)
I believe the answer is:
nifty
'agile' is the definition.
(I've seen this before)
'fit to be frisky in new york' is the wordplay.
'to be frisky' is an anagram indicator.
'in' is an insertion indicator.
'new york' becomes 'ny'.
'fit' anagrammed gives 'ift'.
'ift' going into 'ny' is 'NIFTY'.
(Other definitions for nifty that I've seen before include "Smart" , "Particularly good (informal)" , "Stylish, nimble" , "Fine (slang)" , "Dandy" .)