Analysis of traces is an increasingly active issue in knowledge discovery (kd). Unfortunately, to date, few tools are designed to help interactively the analyst during the knowledge discovery process. In this paper, we present Transmute, a tool to assist the analyst throughout an interactive kd process in traces. Transmute displays the results of the mining together with the source trace so that it is easier for the analyst to understand them and thus to refine the parameters of the algorithm accordingly. Transmute is developed as a web platform and relies on a Python implementation of the kd process.