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mental model
What the user thinks the system is doing. If the model is wrong, the UI taught the wrong story.
What is mental model?
A mental model is the user’s theory: “send” means it left my machine, “save” means it survived refresh. When the theory and the behavior differ, people make confident mistakes. Copy and structure either match the theory or teach a new one on purpose.
Why does mental model matter when vibe coding?
Models name buttons “Submit” and “Process” and store data in three places. The user cannot predict what will happen. Name the story in one sentence before drawing.
How do you do mental model?
Write the user’s sentence: “I am ___ and this screen ___.” Labels use those nouns. Do not introduce a second word for the same object.
How do you ask a model for mental model?
The user’s mental model is: (one sentence). Use those nouns in the UI. Do not introduce a synonym. The button does what that sentence promises, including what is saved and when.
What goes wrong with mental model?
Teaching a clever model when a boring one would do. Match the tool they already know unless you have a reason not to.