Hello, I've two testers complain that transfers are not working. I can see in the logs that the main greeting assistant understands their intent and declares it is making the transfer, but then it gets stuck Call ID : 9ec7a48f-7f84-43b0-ab65-a6d192381750 Or Call ID : 1444880b-b9b8-4aa5-91cb-f62a56f10224 Is this is a model issue or something else?

There is no documentation indicating that Gemini models themselves block call transfers in Vapi. The most common causes for transfers getting stuck are missing the required

destination

parameter in your transfer tool configuration or issues with your SIP trunk (such as SIP REFER not being enabled). Action: Double-check your transfer tool setup to ensure the

destination

property is present and that your SIP provider supports SIP REFER. If the issue persists, review your call logs for specific error codes or contact Vapi support with your call IDs for further investigation. [See Vapi call forwarding troubleshooting](https://docs.vapi.ai/call-forwarding#troubleshooting) Source: - [Vapi documentation: call forwarding](https://docs.vapi.ai/call-forwarding)

There is no call forwarding, it is a transfer within a squad, from one assistant to another

Suggestion: Double-check your Squad configuration to ensure that each

assistantDestinations

entry has the correct

assistantName

and that the

message

property is set to an empty string for silent transfers. For example:

json
{
  "assistantDestinations": [
    {
      "type": "assistant",
      "assistantName": "NextAssistant",
      "message": "",
      "description": "Transfer to NextAssistant"
    }
  ]
}

Also, confirm that your assistant's prompt includes the correct transfer trigger (e.g.,

trigger the transferCall tool with 'NextAssistant' Assistant

). This setup should work regardless of the model, including Gemini. If the issue persists, review your squad and assistant prompts for any misconfigurations. Sources: - [Vapi documentation: Squads](https://docs.vapi.ai/squads) - [Vapi documentation: Silent Transfers](https://docs.vapi.ai/squads/silent-transfers)

Hi Ouranos, For the transfer issue with Gemini models, ensure the following steps are followed: 1. **Check Assistant Configuration**: Make sure the assistant configurations are set correctly. For silent transfers, verify that

firstMessage

is an empty string and

firstMessageMode

is set to

assistant-speaks-first-with-model-generated-message

. 2. **Verify Transfer Steps**: - Ensure the transferCall tool is set correctly in the assistant's prompt with the correct assistant name. - Confirm that the destination assistant proceeds directly to the Task section without greetings or small talk. 3. **Inspect Logs**: Check logs for any errors or incomplete steps, especially around the transfer trigger and destination actions. 4. **Review Model Settings**: If using the Gemini models, consider reviewing advanced settings such as

realtimeConfig

to fine-tune real-time capabilities. If the configuration is correct but the transfer still gets stuck, try switching to a different model to see if the issue persists. Also, make sure there are no network issues that might be causing a delay or failure in transferring the call. You can refer to the [Silent Transfers documentation](https://docs.vapi.ai/documentation/core-concepts/squads/silent-transfers) for more detailed setup steps.

I don't understand the first message is an empty string part. My assistants all have first messages and this has never been an issue before. In general this seems to be something that broke recently, as it was working fine until now

For silent transfers to work reliably in Vapi squads (including with Gemini models), set the destination assistant's

firstMessage

to an empty string and

firstMessageMode

to `assistant-speaks-first-with-model-generated-message`:

json
{
  "firstMessage": "",
  "firstMessageMode": "assistant-speaks-first-with-model-generated-message"
}

This ensures a seamless, uninterrupted transfer. If your assistants have non-empty first messages, try updating this setting and retest the transfer flow. Reference: [Silent Transfers documentation](https://docs.vapi.ai/squads/silent-transfers) Source: - [Vapi documentation: Silent Transfers](https://docs.vapi.ai/squads/silent-transfers)

I don't want a silent transfer, I'm not sure why you are recommending this?

You do not have to use silent transfers if you want the user to hear a transfer announcement. To configure a non-silent transfer between assistants in a squad, set the

message

property in your

assistantDestinations

to your desired announcement:

json
{
  "assistantDestinations": [
    {
      "type": "assistant",
      "assistantName": "NextAssistant",
      "message": "Please hold while I transfer you to our appointment booking assistant.",
      "description": "Transfer to NextAssistant"
    }
  ]
}

This will play the message to the user during the transfer. Silent transfers are just an option, not a requirement. If your non-silent transfers have stopped working, the issue may be elsewhere in your configuration or platform behavior, not because silent transfers are now mandatory. Sources: - [Vapi documentation: Squads](https://docs.vapi.ai/squads) - [Vapi documentation: Silent Transfers](https://docs.vapi.ai/squads/silent-transfers)

Can you please try gpt-4o and see how it goes?

Just tried that, same problem Call ID : 5027ab2d-689e-4860-8fc6-450fa9316f86

If your non-silent assistant-to-assistant transfers are still getting stuck, double-check that your

assistantDestinations

entry includes a non-empty

message

property, like this:

json
{
  "assistantDestinations": [
    {
      "type": "assistant",
      "assistantName": "NextAssistant",
      "message": "Please hold while I transfer you to our appointment booking assistant.",
      "description": "Transfer to NextAssistant"
    }
  ]
}

If this is already set and the issue persists (even with gpt-4o), please review your call logs for error codes and share them with Vapi support for further investigation, as this may indicate a platform issue rather than a configuration problem. Sources: - [Vapi documentation: Squads](https://docs.vapi.ai/squads) - [Vapi documentation: Silent Transfers](https://docs.vapi.ai/squads/silent-transfers)

Hi Ouranos, can you book a quick call with kyle? He can help you out with it https://cdn.discordapp.com/attachments/1375466666124906508/1376458044615168012/image.png?ex=683565f3&is=68341473&hm=4ee36ef1434b5e3db9bf43ad6f5606ce3815d293d233db4c7098b1e7ab71c5f7&

Yes, thank you!

To ensure a non-silent assistant-to-assistant transfer in your Vapi squad, set the

message

property in your

assistantDestinations

to your desired announcement. For example:

json
{
  "assistantDestinations": [
    {
      "type": "assistant",
      "assistantName": "NextAssistant",
      "message": "Please hold while I transfer you to our appointment booking assistant.",
      "description": "Transfer to NextAssistant"
    }
  ]
}

If this is already configured and transfers are still not working, please review your call logs for errors and share them with support, as this may indicate a platform issue rather than a configuration problem. Sources: - [Vapi documentation: Squads](https://docs.vapi.ai/squads) - [Vapi documentation: Silent Transfers](https://docs.vapi.ai/squads/silent-transfers)