A list dutifully worked on (4)
I believe the answer is:
rota
'a list' is the definition.
(rota is a kind of list)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for rota that I've seen before include "List assigning turns of duty" , "List of duties to be done, or people to do them" , "Duty roster" , "Task list, roster" , "Roll call or roster" .)