Songs of Carlo's composition? (6)
I believe the answer is:
carols
'songs' is the definition.
(carol is a kind of song)
'carlo's composition?' is the wordplay.
'composition?' is an anagram indicator (letters arranged or composed in a different order).
'carlos' is an anagram of 'CAROLS'.
'of' is the link.
(Other definitions for carols that I've seen before include "Traditional Christmas songs" , "Special songs for Christmas" , "Seasonal songs" .)