Morgan, when entertaining live, is a tool (6)
I believe the answer is:
pliers
'tool' is the definition.
(pliers is a kind of tool)
'morgan when entertaining live' is the wordplay.
'morgan' becomes 'piers' (Piers Morgan).
'when entertaining' is an insertion indicator.
'live' becomes 'l' (electrical abbreviation).
'piers' going around 'l' is 'PLIERS'.
'is a' acts as a link.
(Other definitions for pliers that I've seen before include "Workmen's tools" , "Kind of pincers with flat gripping surfaces" , "taxi-drivers, say" , "Wire benders" , "Nippers" .)