Ask HN: chatGPT but for a company's knowledge base?

We're currently looking for a suitable knowledge management tool and after being blown away by chatGPT's comprehension of natural language, I'm wondering if something exists that:

- uses a language model to improve discoverability

- is GDPR compliant (ideally open-source or self hosted)

- does not make stuff up but links to the relevant knowledge base article

- supports versioning of articles

- simple text based format (like markdown)