** {{flowInstanceId}} set to the flow instance identifier retrieved from the incoming request,
** {{flowStepId}} set to an UUID value,
** {{flowStepInterfaceName}} set to the service provider interface name,
** {{flowStepServiceName}} set to the service provider service name,
** {{flowStepOperationName}} set to the operation of the invoked service provider,
** {{flowStepEndpointName}} set to the service provider endpoint name,
** {{flowPreviousStepId}} set to the step identifier of the previous step, retrieved from the incoming request.
* on service provider termination, when returning the outgoing response, with following attributes:
** {{traceCode}} set to {{provideFlowStepEnd}} or {{provideFlowStepFailure}},
** {{flowInstanceId}} set to the flow instance identifier retrieved from the incoming request,
** {{flowStepId}} set to the flow step identifier defined on incoming request receipt.