Female employed by small task force not meeting required standards (5)
I believe the answer is:
unfit
'not meeting required standards' is the definition.
(not fit for purpose)
'female employed by small task force' is the wordplay.
'female' becomes 'f' (abbreviation).
'employed by' is an insertion indicator (inserted letters used or employed inside).
'small task force' becomes 'unit' (eg a military unit).
'f' inserted within 'unit' is 'UNFIT'.
(Other definitions for unfit that I've seen before include "Unsuitable" , "struggling to keep up?" , "Incompetent" , "Not in good shape physically" , "Not healthy" .)