Short agent on the way to put down new flags (6)
I believe the answer is:
'put down new flags' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'short agent on the way' is the wordplay.
I cannot quite see how this works, but
'agent' could be 'rep' (short for representative) and 'rep' is present in the answer.
'way' could be 'ave' (abbreviation for avenue, a type of 'way') and 'ave' is found within the answer.
No letters remain.
This explanation may well be incorrect...
'to' acts as a link.
Can you help me to learn more?