Create a Databricks workspace on Azure, AWS, or GCP — first-party vs third-party service model differences, why az databricks workspace create is required on Azure (not the Databricks Account API), required vars, RG quota handling, region Default Storage validation, managed resource group purpose, polling, and post-creation profile registration. Use when creating a Databricks workspace, debugging workspace creation failures (subscription type errors, RG quota, unsupported region), or understanding the Azure-first-party vs AWS/GCP-ISV model.