Application-based mapping without an on-premises provisioning app


I have configured an app in OKTA, and I would like to pre-define attribute mappings for my users - using application-based mapping.
My app is not defined as on-premises provisioning.
How can I configure the application-based mapping?

More specifically, I want Okta to send the user provisioning info via SCIM directly to a server of ours on AWS, instead of installing a local agent. How do I do that?