This feature only works during phone calls instead of web calls. It’s available for Retell numbers and imported numbers.
It is common in call operation to transfer the call to another human agent or another AI agent.
1

Add Transfer Call Tool

Click ”+ Add” in the tools section and select “Transfer Call” from the dropdown menu.
2

Configure Basic Settings

Define specific conditions under which the call should be transferred. For example:
  • If the user is angry, transfer the call to a human agent.
3

Update the Prompt

Enhance the agent’s understanding by incorporating the transfer call conditions into the prompt. Include specific instructions such as:“If the user is angry or frustrated, use the transfer_call tool to transfer the conversation to a human agent.”
4

Configure Transfer Type

Choose between cold transfer or warm transfer:
  • Cold transfer: The call is transferred to a destination number and that’s it.
  • Warm transfer: The call is transferred to a destination number, and when connected, AI agent will leave a handoff message. Useful when you want to brief the next agent about previous context.
    • You can configure the handoff message in the format of Prompt or Static Sentence
5

Configure Caller ID for Cold Transfer (Optional)

For cold transfers, you can configure how the caller ID appears to the next agent:
  1. Retell Agent’s number: The transfer destination will see the Retell agent’s number
  2. Transferree’s Number: The transfer destination will see the number that the user is calling from. Please note that you have to configure following in your telephony provider in order to make it work, because this option internally is simply transferring via SIP REFER, and some telephony provider have the ability to set caller id for SIP REFER.
    • enable SIP REFER
    • enable transfer to PSTN
    • set caller id as transferee