Agent commandeers shelter for dwarf (6)
I believe the answer is:
sleepy
'dwarf' is the definition.
(I've seen this before)
'agent commandeers shelter' is the wordplay.
'agent' becomes 'spy' (spy is a kind of agent).
'commandeers' is an insertion indicator.
'shelter' becomes 'lee' (I've seen this before).
'spy' enclosing 'lee' is 'SLEEPY'.
'for' acts as a link.
(Other definitions for sleepy that I've seen before include "Doc's nodding pal" , "over-tired" , "(Of place) low in activity" , "Ready to turn in" , "Feeling like having a snooze" .)