One disclosed example provides a computing system configured to receive input defining a machine conversation dialog flow, display in an editing user interface a first representation of the machine conversation dialog flow in the form of a symbolic representation, receive input requesting display of a second representation of the machine conversation dialog flow, and in response to the request display in the editing user interface the machine conversation dialog flow in the character-based representation. The computing system is further configured to, based upon the machine conversation dialog flow, update a machine conversation schema template to form an updated machine conversation schema, and form an agent definition file based upon the updated machine conversation schema for use in executing the machine conversation dialog flow.