Questions · Buy
The purchase worked. Why is this reported at all?
Because it worked for an agent that reads the page the way a person looks at it. Many agents read the controls a page declares instead, and to them there was no option to choose and nothing to press. The fix is small and the page looks the same afterwards.
Why it happens
Agents read a page in two ways. Some look at it, the way a person does. Many read its structure instead: the buttons, links, select lists and form fields the markup declares, and the names and roles the accessibility tree gives them. That is faster and cheaper, and it is how most automated readers find what to press.
A store that builds its option picker from a styled div, or adds to the cart with a quantity stepper and no add to cart button, works for the first kind of agent and not the second. The scan reports it when the purchase only went through because the walk read the page as a person would.
This comes up at the Buy stage. The full treatment, including how to reproduce it and what to change, is on A control an agent needs is not exposed as one.
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