The e ective use of automated theorem provers is frequently augmented by embedding these systems into interactive proof development environments. However, in order to act as a competent mathematical assistant, which is the ambitious goal behind these interactive extensions of automated provers, these tools behave too passively and in a stereotypic way, because they lack the capability to adequately take into account requirements on proof search control and user demands for their own actions. Motivated by this de cit, we have incorporated several facilities into the mega proof development system that anticipate a number of divergent factors, based on mathematical knowledge, proof search defaults, and expectations about users. The techniques ...