This will be used by unattended processes that deploy the application to Azure, like TeamCity. You'll want to name the App Registration accordingly.
COMPUTER. PUT THEM IN TEAM CITY ONLY
MAKE SURE TO SEGREGATE SERVICES TO KEEP THEM SECURE
fake build --target deploy -e resourceGroupName=COM-Experimental -e subscriptionId=GUID -e clientId=GUID -e environment=experimental -e location=southcentralus -e tenantId=GUID -e clientSecret=SECRETKEY