Human speech signals that are uttered within an environment are transcribed; the environment includes one or more avatars representing one or more software agents; the human speech signals are directed to at least one of the avatars. At least one non-speech behavioral trace is obtained within the environment; the trace is representative of non-speech behavior directed to the at least one of the avatars. The transcribed human speech signals and the at least one non-speech behavioral trace are forwarded to the one or more software agents. A proposed act is obtained from at least one of the agents; responsive thereto, a command is issued to cause the avatar corresponding to the software agent from which the proposed act is obtained to emit synthesized speech and to act visually in accordance with the proposed act.