Hi, this one's a workspace entitlement thing, not something broken in your setup. Agent Bricks (which is what Supervisor Agent is part of) isn't available on Databricks Free Edition. The preview toggle in your settings turns on the UI for it, but saving still checks entitlement server side, and that's where it blocks you with the "contact sales" message. The Free Edition docs list Knowledge Assistant (another Agent Bricks feature) explicitly as unsupported, and Supervisor Agent sits in the same product bucket, so it hits the same wall.
If you want to actually try Supervisor Agent, you'd need a Premium or Enterprise tier workspace with Unity Catalog and serverless compute enabled, plus a serverless usage policy with a nonzero budget attached. A paid trial workspace would get you there faster than pushing on this in Free Edition.
