The paper considers the ability to describe malicious bots using their characteristics, which can be the basis for building models for recognising bot parameters and qualitatively analysing attack characteristics in social networks. The following metrics are proposed using the characteristics of VKontakte social network bots as an example: trust, survivability, price, seller type, speed, and expert quality. To extract these metrics, an approach is proposed that is based on the methods of test purchases and the Turing test. The main advantage of this approach is that it proposes to extract features from the data obtained experimentally, thereby obtaining a more reasonable estimation than the expert approach. Also, an experiment on extracting metrics from malicious bots of the VKontakte social network using the proposed approach is described, and an analysis of the metrics' dependence is carried out. The experiment demonstrates the possibility of metrics extracting and analysis. In general, the proposed metrics and the approach to their extraction can become the basis for the transition from binary attack detection in social networks to a qualitative description of the attacker and his capabilities, as well as an analysis of the evolution of bots.