Hand off the dialog between agents

What for: this guide demonstrates the complete agent collaboration cycle: handoff to a specialist and control returned to the parent.

Problems it solves: the main assistant should not handle every topic, and the user must always see who is replying.

Result: the real chat shows the transfer, a Returns Agent reply, handback, and the next reply from the main agent.

Step 1. Add the returns agent as a tool¶

Open the main agent and add the returns sub-agent from the library. On this chip, Call invokes the sub-agent once and returns its result to the current agent; the main agent remains active.

Step 2. Enable handoff mode¶

Click Call on the chip to switch it to Handoff, then describe when to transfer control. Following user turns are routed to the sub-agent. The current text and explicit variables are passed automatically; message history must be mapped separately when it is needed.

Step 3. Publish and open Run mode¶

Publish the graph and switch to Run. The shared chat used on the agent page and in the embedded widget opens on the right.

Step 4. Hand off the dialog to the specialist¶

Send a return question. The feed shows a dedicated control-transfer card for Агент возвратов. This is not a normal reply: the next user turn is routed to the child agent.

Step 5. Verify that the sub-agent is replying¶

The reply is marked with a blue icon, the Returns Agent name, and the Sub-agent role. Every bubble remains attributable in a long conversation.

Step 6. Return control to the main agent¶

When the task is complete, the child calls handback_to_parent. A handback card is added to the feed. Only the result text and explicitly selected variables are returned — return_id in this example.

Step 7. Verify the return to the main agent¶

Result demonstration. The next reply is again labelled with the main agent name and Agent role. One feed shows the complete cycle: user → agent → handoff → sub-agent → handback → agent.

Summary. Use Call for a one-off invocation, Handoff to route following turns, and handback_to_parent to explicitly return control.