Hi @Scott A -- Cam from the Intercom Support team here!
You’re observation is correct, at present there isn’t a way to add ‘callouts’, like the yellow box in your screenshot, when creating an Article via API. It just isn’t something that is supported at the moment nor is there a viable workaround for this other than manually adding the ‘callouts’ from within the Workspace UI (less than ideal I know).
The ability to add ‘callouts’ when an Article is created by API has come up with other customers previously and has been submitted as a Feature Request to our Product Development team - I’ll go ahead and add you to the FRQ so the team is aware of your interest in this. Hopefully it’s something we see added in the near-future
Hope that at least helps clarify whats possible at the moment!