The use of OPACs has been one of the problems that users of libraries have faced. The application of Web 2.0 techniques in OPACs has favored the interaction between users and library automation systems. However, these improvements focus on aspects of collaboration and recommendation rather than on aspects of cognitive work. In this field, the contribution of software agents can be of great importance. This chapter presents the design of an intelligent personal assistant called Byblon, which uses programming of agents and semantic queries against repositories. The aim of the personal assistant is to offer users recommendations on concepts related to the object of his search. The user evaluation has provided satisfactory results, and the use of an avatar as a future interface development is envisioned.