Ask HN: Has anyone adopted or seen adoption of RFC8959 secret-token?

That particular structure hasn't really taken off, but the general idea of having unique-ish token formats that can be mapped back to a provider is becoming more popular.

Trivy has a pretty good collection of examples that is used for its secret scanning functionality, https://github.com/aquasecurity/trivy/blob/main/pkg/fanal/se....

I don't think the idea is so much that API users understand its purpose so much as that repository hosts like Github can scan for it automatically. We don't use secret-token, but we do use a very identifiable fixed constant string prepended to our tokens, for similar reasons.