cannot look up API documentation for "authentication"

(1) This page: https://developer.atlassian.com/bitbucket/api/2/reference/search?q=authentication

Gives no results for "authentication"

I expected it to find at least this page:
https://developer.atlassian.com/bitbucket/api/2/reference/meta/authentication

(2) Additionally, your API Reference pages, such as this one (below), do not have any mention of authentication. The Bitbucket API is unusable without it.

https://developer.atlassian.com/bitbucket/api/2/reference/resource/repositories/%7Busername%7D/%7Brepo_slug%7D/src/%7Bnode%7D/%7Bpath%7D