Guide: Writing prompts for AI user testing

AI user testing identifies UX issues before human testing but a specific, actionable prompt is critical to achieve real insights. ‘Good’ Velocity prompts will constrain a simulation with specific testing goals for your design. Constraints are key since Velocity AI isn't thinking; it is acting on what looks most likely based on patterns from millions of examples.
  1. Be super specific
  2. Focus on one action, one goal
  3. Examples: Ideal prompt format for common test challenges

1. Be super specific

Simulations are not mind-readers, they need a crystal-clear goal. Vague prompts lead to vague results.
  • ❌ Bad Prompt: "Explore the app."
  • ✅ Good Prompt: "Sign up for a new account using the email address user@test.com you are successful when you view a notification saying thanks for signing up"
"Explore" is too broad. What are they exploring for? When will they be finished? Simulations need a specific challenge with a measurable outcome of success. You might not immediately know what you are testing for but you can start with ‘exploring’ specific areas of your software’s functionality. For instance, test the efficiency of your sign up process. Tasking 100 simulations with ‘signing in’ will shortcut weeks of incremental testing by showing you how many simulated users successfully signed up, and where others hit a snag. Instant clarity!

2. Focus on one action, one goal

Each prompt should isolate a single action to be conducted then state how the simulation will identify success. This keeps your results clean and makes it easy to pinpoint problems. Don't try to cram too much into one prompt.

  • ❌ Bad Prompt: "Sign up, then browse products, and buy something."
  • ✅ Good Prompt: "Add a loaf of bread to your shopping cart."
In this instance, casting a net across the entire shopping process might be possible but it’s not the best place to start since there are likely too many opportunities for users to drop off to make immediate optimisations. The more steps you add to a single prompt the higher the likelihood for vague and wildly differing results. Velocity encourages you to test as many actions as you can but start one at a time and build outwards. 

3. Examples: Ideal prompt format for common test challenges

Login, sign-up, on-boarding:
  • "Log in to an existing account with the credentials Name:’John Doe’ and email: ‘john@email.com’ you are successful when your email is displayed in the top right navigation"
  • "Create a new user profile with the credentials Name:”John Doe” and email: “john@email.com” you are successful when you receive a notification stating that ‘verification was successful’"
Completing a purchase:
  • "Complete the checkout process for the items in your cart. You are successful when you receive a notification thanking you for your order"
  • "Apply discount code “FREE30” during checkout. You are successful when you receive a notification stating your discount code has been accepted or declined"
Exploration & discovery:
  • "Find the nearest coffee shop on the map. You are successful when the location of one or more coffee shops are displayed"
  • "Locate the 'Help' section within the app. You are successful when you have navigated to an area displaying the titles of the most frequently asked questions"
Revealing unclear interfaces:
  • "Change your notification settings to only send emails when contacted directly by another user. You are successful when you are confident that the notification settings have been saved"
  • "Delete the ‘apples’ from your favorites. You are successful when your favourites are displayed without containing an item titled ‘apples’"

Validate with bold, clear prompts!

See the difference? Writing a specific, actionable prompt with clear action and success criteria is your ticket to a predictable, highly informative outcome from Velocity. This isn't just about making the AI interact; it's about uncovering specific hidden UX bumps that would trip up your real users.
Now, go ahead! Refine your Velocity prompts, we bet you'll be amazed at the immediate insights you get. Velocity's here to ensure every prototype you create is validated long before it ever frustrates a human.
What's the very first prompt you're going to write for your current prototype?

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