Top Five Good Tenets for Writing Prompts

1. State what the application will do and how it will work before engaging callers in conversation. The application needs to set the expectations of the caller and explain the role that it will serve. For example, a rate quote application that is made for people who have never spoken to a computer before would benefit from a phrase like "In a moment, we'll have a short conversation where you'll tell me what you want to ship, and I'll tell you how much it will cost." The caller knows that they'll need to talk to this computer and that the conversation will be short, and the system can provide a shipping rate quote. Sometimes the phrase can be as simple as "Welcome to the United Airlines Flight Information System." This phrase is mainly intended to orient the user , and to prevent them from thinking that they can use the application for other services, such as buying a ticket or redeeming frequent flyer miles.

2. Design to the caller's level of knowledge at each state in the application, understanding that callers will learn terms and procedures as they use an application. Each state of an application should not be designed in isolation. As callers learn how to use a system, the system can take advantage of this to either shorten the length of the prompts, or to provide more information.

3. Use a consistent sentence structure for all commands within a single prompt (for example, "[VERB] the [NOUN]"). Other popular structures include

   [VERB] the [NOUN], as in: "'Make a payment,' 'Check balances ,' and 'Calculate loan amount'"

   [NOUN/NOUN PHRASE], as in: "'Payments,' "Loan calculators ,' and 'Balances'"

   [VERB], as in: "'Delete,' 'Play,' and 'Save'"

4. Ensure that all prompts should have a conversational tone in language and recordings to convey ideas clearly and simply. In general, a well-written prompt doesn't need to have a secondary explanation that attempts to simplify the concept in common parlance. The text should always be natural enough that further explanation of the concept provides additional information rather than simply restating the concept using simplified language.

5. Tell callers only as much as they need to know to make effective decisions ”no more and no less. ^[1] Achieving the balance between too much and too little information can be tricky, but start by erring on the side of too little information so that brevity is achieved. Then examine the prompt to determine if there's something that absolutely cannot be left out.

   ^[1] To learn more about this see H. P. Grice,"Logic and Conversation," in Syntax and Semantics , Vol. 3, Peter Cole and Jerry Morgan, Eds. (San Diego: Academic Press, 1975) pp. 41 “58.