We've merged the comments* to https://news.ycombinator.com/item?id=45152284 and re-upped that one.

(* except the ones that only make sense here)

Does substack let you add canonical URLs for the post? Otherwise won't you penalised by search engines for duplicated content?

I decided I am willing to take that risk.

You should have posted the instructive failures you mention, not just the successes.

This one was meant to be illustrative of a (thought provoking) failure https://simonwillison.net/2025/Sep/6/research-goblin/#histor...

I wondered what "something I’m certain it won’t be able to handle" would look like.

I tried "Is the pelican in her pity unique to English churches or does it show up in France too?" (Easy) followed by "Find places I can see this near nontron in France" (which I anticipated to be extremely hard): https://chatgpt.com/share/68bd9ca1-f6d0-8006-a507-c817857957...

It gave me a result that looked convincing! But I don't trust it. I very much doubt the internet has reliable, comprehensive data about instances of that piece of religious imagery in small churches around this region of France.