Principle:Microsoft Autogen Handoff Termination

Knowledge Sources	Microsoft AutoGen AutoGen Conditions Docs
Domains	Multi-Agent Systems, Termination Conditions, Human-in-the-Loop, Workflow Control
Last Updated	2026-02-11 00:00 GMT

Overview

Handoff termination is a stopping condition that halts a multi-agent conversation when a specific agent is designated as the handoff target, enabling controlled exit points and human-in-the-loop workflows.

Description

Multi-agent swarm systems need well-defined stopping conditions. While some termination conditions are based on message counts or content patterns, handoff termination addresses a distinct need: stopping execution when control is transferred to an entity outside the swarm, most commonly a human user.

In a swarm, agents continuously hand off tasks to each other. This creates a potential infinite loop if no stopping criterion is defined. Handoff termination solves this by monitoring the message stream for a HandoffMessage whose target matches a preconfigured name. When detected, it emits a StopMessage that signals the orchestrator to halt the conversation.

The most common use case is the human-in-the-loop pattern:

• An agent is configured with a handoff to a pseudo-agent named "user" (or any designated name).
• A handoff termination condition monitors for transfers to "user".
• When the agent determines it needs human input, it invokes the "user" handoff.
• The termination condition fires, pausing the swarm.
• The human provides input, and the swarm is resumed with that input as a new task.

This principle extends beyond human interaction. Any external system, approval gate, or asynchronous process can be modeled as a termination-triggering handoff target.

Usage

Use handoff termination when:

• You need to pause a swarm to collect human input before continuing.
• A workflow requires an approval gate where an external system must intervene.
• You want to create breakpoints in a multi-agent conversation at specific transfer points.
• You need to combine handoff-based stopping with other termination conditions (e.g., max messages) using logical operators.

Theoretical Basis

Handoff termination implements the sentinel pattern in stream processing. The message stream is continuously scanned for a sentinel value (a HandoffMessage with a specific target), and when found, the stream is terminated.

Handoff Termination Algorithm:

State: terminated = False

On receiving message batch M = [m_1, m_2, ..., m_n]:
  IF terminated:
    RAISE TerminatedException

  FOR each message m_i in M:
    IF m_i is HandoffMessage AND m_i.target == configured_target:
      terminated = True
      RETURN StopMessage(
        content="Handoff to {target} from {m_i.source} detected.",
        source="HandoffTermination"
      )

  RETURN None  (no termination triggered)

Reset:
  terminated = False

Key properties of this design:

• Single-shot: Once triggered, the condition remains in the terminated state until explicitly reset. Attempting to evaluate after termination raises an exception.
• Composable: Can be combined with other termination conditions using logical OR (|) operators, allowing expressions like HandoffTermination("user") | MaxMessageTermination(10).
• Resettable: The reset() method allows the condition to be reused across multiple runs of the same swarm, which is essential for the resume-after-human-input pattern.

Related Pages

Implemented By

• Implementation:Microsoft_Autogen_HandoffTermination_Init