Not long tunes I'm composing (7)
I believe the answer is:
'not long tunes i'm composing' is the definition.
I can't tell whether this defines the answer.
'tunes i'm composing' is the wordplay.
'composing' indicates anagramming the letters.
'tunesim' anagrammed gives 'MINUTES'.
Can you help me to learn more?
(Other definitions for minutes that I've seen before include "Records" , "summary" , "Units of time" , "Recorded notes of a meeting" , "Written account of a meeting" .)