In one embodiment, a method includes receiving, from a client system associated with a user, a user request comprising a reference to a target object, accessing visual data from the client system, wherein the visual data comprises images portraying the target object and one or more additional objects, and wherein attribute information of the target object is recorded in a multimodal dialog state, resolving the reference to the target object based on the attribute information recorded in the multimodal dialog state, determining relational information between the target object and one or more of the additional objects portrayed in the visual data, and sending, to the client system, instructions for presenting a response to the user request, wherein the response comprises the attribute information and the determined relational information.