Green’s Dictionary of Slang

a pickpocket.

1859, 1860		Hotten Dict. of Modern Sl. etc.
1873		Sl. Dict.
1882		Star (Guernsey) 23 Feb. 4/2: Akin to the cly-fakers are the toolers who use knives to slit open pockets, and scissors to snip watch chins in two.
1895		Crowe Aus. Sl. Dict. 87: Tooler, a pick pocket.