Mind reader's claim (3)
I believe the answer is:
esp
'mind reader's claim' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for esp that I've seen before include "Initially, clairvoyance or telepathy" , "Second sight (abbr)" , "Apparent power to perceive things that others can't, initially" , "Apparent power to perceive things that others can't, in short" , "Extrasensory perception (abbrev.)" .)