1. A computer-implemented method comprising: receiving, by a computer-implemented agent specific to a user device, a digital representation of speech encoding an utterance; determining, by the computer-implemented agent, that the utterance specifies a request for another computer-implemented agent represented by data, stored on the user device, that identifies a particular style of expression for the other computer-implemented agent from among two or more different styles of expression for a particular language; receiving, by the user device, identification of a response to the utterance from the other computer-implemented agent; determining, by the user device, the particular style of expression for the other computer-implemented agent to use for presentation of the response; and presenting, by the user device, the response to the utterance received from the other computer-implemented agent according to the particular style of expression.
16. The method of claim 1 wherein determining, by the computer-implemented agent, that the utterance specifies a request for the other computer-implemented agent comprises determining, by the computer-implemented agent, that the utterance specifies a requirement to establish a communication with the other computer-implemented agent, the method comprising: establishing, by the user device, a communication between the other computer-implemented agent and the user device prior to receiving the identification of the response to the utterance from the other computer-implemented agent and in response to determining that the utterance specifies a requirement to establish a communication with the other computer-implemented agent.