Abstract: A computer-implemented method of controlling an output from a dialogue system, the method comprising: receiving, by way of an input, first input data relating to speech or text provided by a user; selecting a first state from a plurality of states of a deterministic model, at least some states of the plurality of states being associated with a corresponding portion of a language model prompt including an instruction to call a corresponding function; responsive to the first state being associated with a corresponding portion, generating a first language model prompt comprising at least part of the corresponding portion associated with the selected first state; providing the first language model prompt as input to a language model to generate a first language model output; determining whether to execute a function based on the first language model output; responsive to determining to execute a first function based on the first language model output, executing the determined first function to generate a first