Also called: AI bot
The companies run separate bots for separate jobs. OpenAI, for example, uses OAI-SearchBot for ChatGPT search, ChatGPT-User when a person asks ChatGPT to visit a page, and GPTBot for training data.
That split matters: you can block training bots and still allow the search bots that recommend you. Each bot is addressed by its user agent in robots.txt.