brilliant-orangeB
VAPI•6mo ago
brilliant-orange

`transferCall` Tool Not Working with Squad Containing Multiple Assistants

Hi VAPI team,

I'm encountering an issue where the transferCall tool does not work correctly when the call is started using a squad that includes multiple assistants.

Problem Description
When I initiate a call with a squad that contains more than one assistant, the transferCall tool (which is configured to call our server for routing) stops functioning as expected.
It appears that VAPI gets confused between:
An assistant-to-assistant transfer (via the squad), and
A transferCall tool execution that should be handled by our backend via a custom URL.

Current Behavior (with multiple assistants in squad)
When more than one assistant is included in the squad, the transferCall tool that should trigger our backend stops working altogether.
It seems like VAPI is incorrectly interpreting this as a squad member handoff or internal assistant transfer, rather than a tool-based call.

Example Payload Used for assistant-request
{
  "squad": {
    "members": [
      {
        "assistantId": "f4415bca-e04f-427a-a15f-5833ff3c9002",
        "assistantOverrides": {
          "variableValues": {
            "quote_assistant": "Will QA 592dd5-021774"
          }
        },
        "assistantDestinations": [
          {
            "type": "assistant",
            "assistantName": "Will QA 592dd5-021774",
            "message": "",
            "description": "Transfer the user to the quote assistant Will QA 592dd5-021774."
          }
        ]
      },
      {
        "assistantId": "f74dcf3d-d2e8-4fa5-8712-7e41b47b42fe"
      }
    ]
  }
}
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