Close but no cigar:
Although CIA considered many plots (most never advanced beyond the preliminary planning stage) to humiliate or kill Castro including a box of his favorite smokes contaminated with botulinum toxin, a brightly colored exploding seashell, and dusting his shoes with thallium salts to make his beard fall out.
The Agency’s most serious assassination efforts usually involved using someone close enough to the dictator to poison him, Marita Lorenz for example. Check her out if you’re interested (she was in Dallas on 22 NOV ‘63).
In any case it all showcases the CIA’s crashing ineptitude.