The “only when” says if you do a search for Suppliers with the randomly generated key and find more than 1, then they do not have a unique key because more than one supplier has it. If that is the case then he schedules the same workflow to run, and it will continue to loop through until the Supplier being passed through is the only one in the database with that key. Also, the endpoint is just the name of the API workflow so in your picture, you have an endpoint and it is ‘assign-order-number’.