Judge the ability of small fools (6)

I believe the answer is:

assess

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'judge' is the definition.
(to assess is to judge or rate)

I cannot understand how the remainder of the clue works.

(Other definitions for assess that I've seen before include "Evaluate worth" , "Judge the quality of" , "Evaluate (quality)" , "Remedy for all ills" , "Weigh up, estimate value" .)

I've seen this clue in the Evening Standard.

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