1. One or more computer-readable media storing computer-executable instructions that, when executed on one or more processors, cause the one or more processors to perform acts comprising: causing display of a conversation user interface in conjunction with a site of a service provider; receiving input from a user while the user engages in a session on the site of the service provider, the user input comprising one of audio input, keypad input, or touch input; representing the user input in the conversation user interface; determining a response to the user input; representing the response in the conversation user interface; enabling the user to interact with the conversation user interface to ascertain how the response was determined and to modify assumptions used to determine the response; determining a revised response based on the modified assumptions; and representing the modified response in the conversation user interface.