task cannot have both a deadline and destination due to miss

Error message

task cannot have both a deadline and destination due to missing outbound timer queue implementation

What it means

Error "task cannot have both a deadline and destination due to missing outbound timer queue implementation" thrown in temporalio/temporal.

Source

Thrown at service/history/workflow/task_generator.go:992

	}

	// Task is invalid at generation time.
	// This may happen during replication when multiple event batches are applied in a single transaction.
	if err := task.Validate(ref, node); err != nil {
		return nil
	}

	taskInfo := &persistencespb.StateMachineTaskInfo{
		Ref:  ref,
		Type: task.Type(),
		Data: data,
	}
	// NOTE: at the moment deadline is mutually exclusive with destination.
	// This will change when we add the outbound timer queue.
	if task.Deadline() != hsm.Immediate {
		if task.Destination() != "" {
			// TODO: support outbound timer tasks.
			return fmt.Errorf("task cannot have both a deadline and destination due to missing outbound timer queue implementation")
		}
		TrackStateMachineTimer(mutableState, task.Deadline(), taskInfo)
	} else if task.Destination() != "" {
		mutableState.AddTasks(&tasks.StateMachineOutboundTask{
			StateMachineTask: tasks.StateMachineTask{
				WorkflowKey: mutableState.GetWorkflowKey(),
				Info:        taskInfo,
			},
			Destination: task.Destination(),
		})
	} else {
		// TODO: support "transfer" tasks - immediate without destination.
		return fmt.Errorf("task has no deadline or destination")
	}

	return nil
}

View on GitHub (pinned to bde624efd1)

When it happens

Trigger: Thrown at service/history/workflow/task_generator.go:992 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of temporalio/temporal@bde624efd1 (2026-09-01). Data as JSON: /api/errors/a9c8fcb4585d0846. Report an issue: GitHub.