According to report, not out always to be brief (2,3)
I believe the answer is:
in sum
'be brief' is the definition.
(thesaurus)
'according to report not out always' is the wordplay.
I cannot quite see how this works, but
'not out' could be 'in' ('in' is the opposite to 'out') and 'in' is found in the answer.
The remaining letters 'sum' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Other definitions for in sum that I've seen before include "to put it briefly" , "In short" , "All things considered" .)