So I think that in general, if there’s an error then the place where I’m displaying the data (the table or the repeating group, or the text field) will simply be blank. I don’t think the “unhandled error” trigger will work. When you use that trigger you get this choice (i.e. it suggests it will only catch errors related to workflows).
Furthermore, in the actions which I create under this “unhandled error” workflow, I can’t access the API error response. So, for example, I have no way to record the API error message that came back.