Earlier quoted context omitted.
If you want to really test this, search/replace the names with your own random ones and see if it lists those. Otherwise, LLMs have most of the books memorised anyway: https://arstechnica.com/features/2025/06/study-metas-llama-3...
Couldn't you just ask the LLM which 50 (or 49) spells appear in the first four Harry Potter books without the data for comparison?
full transcript: pastebin.com/sMcVkuwd