Congratulate prompt during Kismet? (10)
I believe the answer is:
felicitate
'congratulate' is the definition.
(I know that congratulate can be written as felicitate)
'prompt during kismet?' is the wordplay.
'prompt' becomes 'elicit' (I've seen this in another clue).
'during' means one lot of letters goes inside another.
'kismet?' becomes 'fate' (kismet is a kind of fate).
'elicit' put within 'fate' is 'FELICITATE'.
(Other definitions for felicitate that I've seen before include "Give best wishes to" , "toast" , "Praise" .)