Put the most important information first

When providing requested information, put at the beginning of the prompt the most important elements of the system’s response. (And “important” is what the user wants to hear first, not what the company wants the user to hear.) Otherwise, you will risk having the user interrupt the prompt and miss the important information they were seeking.

Remember that the user will mimic the system

When you design your prompts, keep in mind that the user will be listening carefully to the language spoken by the system. If the system uses stiff, robotic, or verbose, language, so will the user. The user will also closely mimic the very wording used by the system. This can cut both ways. First, make sure that if you have to use slang or jargon, that your grammar includes such slang or jargon. By the same token, if you want the user to use specific phrases or adopt a certain style of responding to your questions, all you have to do is write the prompts in language that implicitly illustrates to the user how you want them to speak.

Use language that is commonly used in conversation

The closer to a human agent’s language you can make your application sound, the more usable it will be. This is not a call to try to fool the user into thinking that they are talking to a real human being. Rather, it is a modest suggestion to avoid having the system speak say things that a human being would never say in normal circumstances. Don’t be tempted with formal, cramped language, or language that reads nicely but would never be spoken by a socially competent human being.

Here is a bad prompt:

System: Please tell me the date of your birth, including the month, day, and year.

Here is a better prompt:

System: What is your birthday?