I've written an IDE in JS where all internal structures are available in the runtime which can be hooked into. I can however not see the usability in what the a

I've written an IDE in JS where all internal structures are available in the runtime which can be hooked into. I can however not see the usability in what the article describe. So I would like to se some practical examples. What if you could do queries like in the article, what sort of queries would you run !?