Sometimes I get the whole wordpress site with ~20 plugins installed from customer, so it is huge codebase. But if customer tells me "i need to fix this button not sending this or that" that all what I copy to cursor and I have the fix on the first try almost every time.
I don't need to inform AI about anything more. Cursor figures it out itself: that it is wordpress, which plugins it has, which plugin is responsible for that button and how to fix it (mostly as filter/action to be added to the theme, sometimes creates custom tiny plugin)
The is also debug mode in cursor but I don't need it in that case. It is helpful when you are working on a new feature but at some point cursor stucks and can't produce what you ask. Then I switch to debug mode and wait when it fix it.