A tool has a tool carrier having a tool cassette with a main body, into which an insert seat for receiving the exchangeable cutting insert is recessed and which has a guide, extending along a direction of adjustment, for an adjusting element for adjusting the position of the main body in the cassette seat in the direction of adjustment. The main body has a first mating surface and at least one second mating surface, wherein the first mating surface extends transversely to the direction of adjustment and the second mating surface extends in the direction of adjustment, and the mating surfaces are configured for the precisely fitting contact against a corresponding first and second contact surface of the cassette seat.
