In tirreno (our product), we catch every resource request on the server side, including LLMs.txt and agents.md, to get the IP that requested it and the UA.
What I've seen from ASNs is that visits are coming from GOOGLE-CLOUD-PLATFORM (not from Google itself), and OVH. Based on UA, users are: WebPageTest, BuiltWith, and zero LLMs based on both ASN and UA.
1. https://github.com/tirrenotechnologies/tirreno