You just curl the site or use its API, if it has one? Then you store the result in a database and see if its value has flipped. I don't get the question; this is trivial.

> Additionally, YesNotice will provide an estimated availability timeline for the question, so you can have some information about when to expect the change.

How is that trivial in the general case?

And how exactly does it call any arbitrary API or know which site to curl for any arbitrary question a user might ask? Your answer doesn’t contemplate the how this actually works.

> YesNotice works by periodically checking the status of the item you care about (e.g., product stock, website availability, domain status) and comparing it to the previous status. When it detects a change from no to yes, it sends you a notification via email.

How does it generalize arbitrary indications of status into yes/no?

How does it know how to use arbitrary APIs to obtain arbitrary indications of status?

That's if the website you're querying is a static html file but the web is much more dynamic and varied. Some of the questions I have: does yesnotice execute js, does it handle an answer appearing on a different page, does it handle ambiguous launch language. In essence: how does it work?

what site does it check? what api does it call?

one of the examples is to see if a new coffee shop is opened in town. what's the API to call for that?