Once you have created an AuthClient and a Connection you can start the authentication process and store the generated secret by using the "Start Auth Flow" endpoint. The "Auth Flow Success" method should not be called directly.
The id in the path parameter is the id of the connection.
The request body needed to start the auth flow has:
integrationId: The id of the integration configuration
definition: The id of the integration definition
tenant: The id of an OIH tenant