I don’t think you can customise the Automations to that extent (although I haven't used them much so I might be wrong).

What you could do is instead of calling the Automation, call a workbenchs that is setup:

• As a streaming service, with a textwriter writing the appropriate JSON
• To call/trigger the automation

It does add an extra link in the chain, but may be the only way to achieve what you’re after….

Thanks for the feedback!  Not wanting to impose, but could you provide a basic schematic of what the workbench might look like?

Hi ​@mpittinger, 

I had to build a similar workflow for ArcGIS online. I’ll attach my workspace here. 

This workspace is trigged from a data streaming webhook.  See this article for details as well: https://support.safe.com/hc/en-us/articles/25407519445901-Submitting-a-Job-through-an-FME-Flow-Webhook-URL

Important notes:
 

• This workflow needed a different response based on a GET or POST method. You can delete the TestFilter if that’s not needed.
• I used a Text Writer to send the JSON back to the source. When publishing this workflow, make sure that this writer is registered to the data streaming service when published to Flow. 
• I used the FMEFlowNotifier to send data to an automation. 

Thank you, so much for the feedback and help!  Sincerely appreciated!