The unified cutting tool design system (SPRI) is presented, consisting of three main stages: the formation of types of tools based on shaping kinematics; forming tool types based on different stock cutting schemes; feature-based tool design. The SPRI system is a general algorithm according to which all the main types of cutting tools are designed. Methodological bases of computer-aided tool design are considered, new calculation methods are given, algorithms are given. For tool engineers and process engineers.