Purpose – The purpose of this paper is to present the results in the area of modern computer-aided control system design tools relating to system identification.Design/methodology/approach – The finite-frequency identification method was designed for the needs of active identification. The test signal represents the sum of harmonics with automatically tuned (self-tuned) amplitudes and frequencies where the number of harmonics does not exceed the state space dimension of the plant. The self-tuning of amplitudes is carried out to satisfy those requirements on the bounds of the input and output which hold true in the absence of a test signal.Findings – In this paper, the software implementation of finite-frequency identification method in the system GAMMA is considered. GAMMA is the two-level computer-aided design (CAD) tool for identification and controllers algorithms synthesis for linear plants.Practical implications – The system GAMMA is the complete and really working system.Originality/value – A new structure of the CAD tool for engineers-developers of control systems is proposed and its program implementation is described. The new variant of finite-frequency identification method with self-tuning of identification parameters (test signal and identification time) is considered.