We are currently experiencing a critical issue where our agents are failing to function when invoking the knowledge base. The tool call response says "Unexpected token '<', \"<!DOCTYPE \"... is not valid JSON" Some of the affected agent call IDs are: 019be0bf-d324-7118-826c-1299227f99ba 019be0bd-fc9f-7ccb-9add-a104de4e2315 I can see the same issue raised by other members of the forum today. This seems to be a widespread issue. Could you please look into this urgently? https://cdn.discordapp.com/attachments/1463533337699287124/1463533338383089745/IMG_7501.png?ex=69796d63&is=69781be3&hm=0334daf2813ba1418c4c724d715a2349656947a55c0e48a4f9aa423843cfe969&

Thank you for sharing the error details. The message

"Unexpected token '<', \"<!DOCTYPE \"... is not valid JSON"

usually means your tool's endpoint is returning an HTML error page (such as a 404 or 500), not the required JSON format. According to the documentation, your webhook must always return a valid JSON response and HTTP 200 status—even for errors. Could you confirm if the endpoint URL configured for "defaultQueryTool" is currently accessible and returning the expected JSON structure when called directly (e.g., via curl or Postman)? This will help determine if the issue is with the endpoint itself or with the integration. For further troubleshooting, please review your call logs and API logs in the [Vapi dashboard](https://dashboard.vapi.ai/) and validate your response format using a JSON validator as recommended in the documentation. If you need guidance on the required JSON structure, let me know! Sources: - [Vapi Debugging Documentation](https://docs.vapi.ai/debugging) - [Custom Tools Troubleshooting](https://docs.vapi.ai/tools/custom-tools-troubleshooting)

yep i get the same error today , and if you change the model from gemini 2.0 Flash to Gemini 1.5 Pro i get: [VertexAI.ClientError]: got status: 404 Not Found. {"error":{"code":404,"message":"Publisher Model

projects/angelic-bee-418405/locations/us-central1/publishers/google/models/gemini-1.5-pro

was not found or your project does not have access to it. P

Hey Hashrin, This has been resolved. The query tool was affected by Google Gemini rate limiting on Jan 20-21. Status: Fixed as of Jan 21, 11:30pm PST. Try your query tool again - it should work now. Let me know if you're still having issues. Incident details: https://status.vapi.ai/incident/809181

We’re still experiencing the same error.

Issue isn't resolved yet you can check the status page.