So, it’s correct, but needs additional clarification:
Password
A password can be given to a user or host identity. This is in addition to the initially generated API key.
If you do not know the API key and only have a password, you can hit the /login endpoint of the API which will return your user or host identity’s API key.
API Key
This is always generated anytime a new identity is defined. This is the minimum requirement for an identity to use for authentication. A password can be optionally granted to the identity.
When using an API key with the Conjur API, you will send it to the /authenticate endpoint and if you provide the header Accept-Encoding: base64 a base64-encoded JWT token will be returned which is your session token for the Authorization header going forward.
I cannot speak to Access Token as I’ve never used one before for API calls.
I think the root of my issue is the concept of “Authentication” (used to get the JWT) versus the concept of “Authorization” which grants access (using that JWT) to the requested resource.
So it seems a JWT is required for all API operations aside from Authentication itself.