Eagle-eyed butler is after a non-leadership job (9)
I believe the answer is:
observant
'eagle-eyed' is the definition.
(thesaurus)
'butler is after a non-leadership job' is the wordplay.
I cannot quite see how this works, but
'a' could be 'an' and 'an' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for observant that I've seen before include "Keen-eyed" , "following religious practices" , "Likely to notice" , "(Of music)using conventional keys" , "Quick to notice things" .)