From the documentation:
.2 The user is prompted to authorize the Trusted App (aka client)
If the user is not logged-in into HMISLynk, He/She will be prompted (via the browser) to log-in.
If the user has not already authorized the Trusted App, He/She will be prompted (via the browser) to authorize the Trusted App. This process is called "user consent".
I need to accomplish the authentication without user intervention.