Eager to call artist first (6)
I believe the answer is:
raring
'eager' is the definition.
('raring' can be similar in meaning to 'eager')
'call artist first' is the wordplay.
'call' becomes 'ring' ('ring' can be a synonym of 'call'**).
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'first' means one lot of letters go next to another.
'ring' after 'ra' is 'RARING'.
'to' acts as a link.
(Other definitions for raring that I've seen before include "Very eager (to do something)" , "Eager, impatient" , "Eager (to go?)" , "Very keen (to go?)" , "Agog" .)