The example in the last link you posted is misleading. GPT does not actually crawl the URL. It hallucinates the answer based on the words in the URL itself. Even though it then casts that hallucinated answer neatly into a Pydantic type. Try it with a URL that does not actually exist. Or a pastebin whose link is just some random hash.

The first rule is not to fool yourself. And you are the easiest person to fool. —Richard Feynman about ChatGPT ;-)