Active interfaces for useful software tools

The majority of public domain software tools is endowed with programmer-oriented interfaces and, as a consequence, they are mainly devoted to "hackers" or specialized programmers. This paper concerns the development of an active interface used to make the utilization of a free software for filtering e-mail messages easy. A multi-agent implementation of an interface is proposed that from one side allows the user to easily specify his needs and from another actively reasons on the user's choices to improve the performance of the filtering process.