We’re definitely working on getting you guys some explicit documentation to create some clarity around what can and cannot run locally on your Hub. I know that @slagle made some mentions of this a while back, and maybe he can weigh in on where that project is at right now.
JD has things right for now, but we are working to add more functionality.
Here are a couple of helpful links for you guys:
https://graph.api.smartthings.com/localInstalledSmartApp/list
https://graph.api.smartthings.com/localDevice/list
These will list your locally installed SmartApps and devices respectively. If your device or SmartApp doesn’t show up in that list, it’s not running locally.