method

Test the consumer product as well as the API

A provider's developer API and its consumer chat product are different systems, and on the same day about the same site they answered differently: the API found the page, the chat product cited fifteen sources and reached none of them (the same observation, in reach). Automating against the API and concluding you are fine is a common and expensive mistake, and it is the one this loop is easiest to get wrong, because the API is the surface that is convenient to script.

Use a fresh or incognito session. An account with history on your project is not a cold reader, and the whole value of the exercise is that it is cold.