Brief Kipling novel carried by Observer (6)
I believe the answer is:
skimpy
'brief' is the definition.
(skimpy means short or brief)
'kipling novel carried by observer' is the wordplay.
'kipling novel' becomes 'kim' (I've seen this before).
'carried by' indicates putting letters inside.
'observer' becomes 'spy' (I can't explain this - if you can you should give a lot more credence to this answer).
'kim' put inside 'spy' is 'SKIMPY'.
Can you help me to learn more?
(Other definitions for skimpy that I've seen before include "Inadequate (of clothing)" , "'Scanty, barely enough (6)'" , "Scanty or mean" , "Providing little coverage" , "Meagre; (of clothes) short and revealing" .)