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# Validate Background Sound URL

POST https://api.vapi.ai/assistant/background-sound/validate
Content-Type: application/json

Reference: https://docs.vapi.ai/api-reference/assistants/assistant-controller-validate-background-sound-url

## Authentication

- `Authorization` header (bearer token, required) — Authenticate server-side requests with a private Vapi API key. Create or copy a key from the [Vapi Dashboard](https://dashboard.vapi.ai) and send it in the `Authorization` header as `Bearer <token>`. Keep private API keys out of client-side code and public repositories.

## Request

### Body (application/json)

This endpoint expects a ValidateBackgroundSoundUrlDTO.

- `url` (string, required) — This is the background sound URL to validate. The server performs a ranged request and checks that the URL serves a live media file.

## Response

### 200

- `valid` (boolean, required) — Whether the URL currently serves a live media file. When false, calls configured with this URL silently play no background sound.
- `reason` (enum, optional) — Why validation failed. Only present when valid is false.
  - Allowed values: `invalid-url`, `blocked-address`, `unreachable`, `timeout`, `too-many-redirects`, `http-error`, `not-audio`
- `status` (double, optional) — The HTTP status the URL returned, when a response was received.
- `contentType` (string, optional) — The content-type the URL returned, when a response was received.

## Examples

**Request**

```json
{
  "url": "https://example.com/my-sound.mp3"
}
```

**Response**

```json
{
  "valid": true,
  "reason": "invalid-url",
  "status": 1.1,
  "contentType": "string"
}
```