The document discusses using a Mule ESB until successful scope component. The until successful scope will retry processing a message until it succeeds or reaches the maximum number of retries. It provides examples of using it for calling web services, database operations, and subflows. It also describes the key attributes like max retries, milliseconds between retries, and failure expression. The document concludes by providing XML code for a flow that uses an until successful scope to retry an HTTP request until it receives a 200 response code.