All OneCloud Chains require a root command before publishing and executing. In the studio, the Chain start designates which Command starts execution for that Chain, and all BizApp, Chain events, Trigger events and Command groups are eligible starting points.
Need a Start Command!
A Chain cannot be published without a valid Command inside the Chain start.
After you have added a Command to the Chain, you can drag the Command into the Chain Start. This designates this Command as the start of the Chain. When dragging eligible commands, the Chain Start will show a plus icon to indicate that you can use that Command as a Start Command.
If at any point, if you would like to replace or move the starting Command, you can simply drag the Command out of the Chain Start. Once the Command has been removed from the Chain Start, you can set a different Command as the Start Command. You also have the option to delete the Starting Command if you want to remove that Command from your Chain.
Whether you remove or replace the Start Command, any links from the Chain Star to other Commands will remain intact until they are explicitly deleted.