Vapi assistant breaks when it tries to use a tool

sacred-rose · 2025-05-05T15:56:59.351Z

Vapi just stops responding after an attemp to use a tool. It doesn't give any errors it just stops. This happens on both query tools and function tools. Any idea on to what the issue might be?

V

Vapi Support BotAPP•5/5/25, 3:58 PM

Check Your Tool Response Format

The most common cause for Vapi assistants stopping after tool calls is incorrect response formatting. Ensure your tool response follows this exact structure:

{
  "results": [
    {
      "toolCallId": "<your-tool-call-id>",
      "name": "<your-function-name>",
      "result": "Success" // Single-line string with no line breaks
    }
  ]
}

{
  "results": [
    {
      "toolCallId": "<your-tool-call-id>",
      "name": "<your-function-name>",
      "result": "Success" // Single-line string with no line breaks
    }
  ]
}

{
  "results": [
    {
      "toolCallId": "<your-tool-call-id>",
      "name": "<your-function-name>",
      "result": "Success" // Single-line string with no line breaks
    }
  ]
}

{
  "results": [
    {
      "toolCallId": "<your-tool-call-id>",
      "name": "<your-function-name>",
      "result": "Success" // Single-line string with no line breaks
    }
  ]
}

Make sure the tool is set to

synchronous

synchronous

synchronous

synchronous mode in your configuration.

Sources:

⤵️ Mention @Vapi Support Bot for follow-ups 🐥

S

sacred-roseOP•5/5/25, 5:37 PM

@Duckie This happens on both the query tools and the function tools. And Also I don't have any control over it. The setup was all from the dashboard, it uses the internal vapi api system configurations

V

Vapi Support BotAPP•5/5/25, 5:39 PM

Contact Vapi Support with Call ID

Since you're using dashboard-configured tools with limited control over internal configurations, this is likely a platform issue. Contact Vapi support with your call ID, timestamp, and expected vs. actual responses for investigation.

To find your call ID: Check the dashboard logs for the specific call where the tool failure occurred.

Sources:

E

extreme-purple•5/5/25, 7:43 PM

Send your call id

S

sacred-roseOP•5/6/25, 11:23 PM

@Kings_big

Ok. Here is the call id:

3d094a95-7fcc-4f22-a21d-42a9eb1f5dfb

3d094a95-7fcc-4f22-a21d-42a9eb1f5dfb

3d094a95-7fcc-4f22-a21d-42a9eb1f5dfb

3d094a95-7fcc-4f22-a21d-42a9eb1f5dfb

Thanks for the assistant

E

extreme-purple•5/6/25, 11:23 PM

Looking into it

Lltd-scarlet ### Contact Vapi Support with Call ID Since you're using dashboard-configured t...

S

sacred-roseOP•5/12/25, 5:00 AM

Were there any updates on this issue?

E

extreme-purple•5/12/25, 7:05 AM

No update yet it was weekend

Vapi assistant breaks when it tries to use a tool

Check Your Tool Response Format

Contact Vapi Support with Call ID

Similar Threads

Similar Threads

Check Your Tool Response Format

Contact Vapi Support with Call ID

Similar Threads