This is what it looks like to be doing the work. Mintlify's own docs set - a docs platform whose premise is "built for both humans and AI" - passes all the Agent-Friendly Docs checks I've implemented so far, save one.
Mintlify's docs return "soft" 404s (returning a 200 with "no content" for a page that doesn't exist instead of a clearly actionable 404). But this is pretty minor, easily fixed, and would only affect a small subset of content in practice.
The fact that they're already doing all the things I identified as important for agent friendly docs means they - and their customers - are ahead of the curve. This is how you spot the real deal, folks.
(Also, now I have a "known good" docs set to test my tooling against as I continue to add checks 😁)