Issue: Error Responses Not Reaching AI Agent in Vapi

I'm experiencing an issue where error responses (non-200 status codes) from my webhook aren't properly reaching the AI agent.

The Issue

  • When the webhook returns a 200 status code, everything works fine
  • When the webhook returns a 400/500 status code with an error message in the response body, the AI agent doesn't seem to receive the error message
  • In the logs, I can see the error response being sent correctly, but the AI doesn't acknowledge it
## What I've Tried
  • I've formatted error messages with an "ERROR:" prefix to make them more visible
  • I've confirmed the error responses are properly formatted according to the Vapi API docs
  • I've verified the responses are being sent with the correct Content-Type header
## Example Response (400 Bad Request)
```json
{
"results": [
{
"toolCallId": "call_abc123",
"result": "ERROR: Missing required parameters: Email. Please provide all required information to find available appointment times."
}
]
}
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