> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vast.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# Authentication

# Authentication

The VastCap API uses API keys to authenticate requests. You can view and manage your API keys in your [VastCap Dashboard](https://captcha.vast.sh).

Your API keys carry many privileges, so be sure to keep them secure. Do not share your API keys in publicly accessible areas such as GitHub, client-side code, etc.

## API Key Authentication

All API requests must include your API key in the request body as `clientKey`.

```json theme={null}
{
  "clientKey": "YOUR_API_KEY"
}
```

## Example Request

```bash theme={null}
curl -X POST https://captcha.vast.sh/api/solver/getBalance \
  -H "Content-Type: application/json" \
  -d '{
    "clientKey": "YOUR_API_KEY"
  }'
```

## Error Responses

If authentication fails, you'll receive one of the following errors:

* `ERROR_KEY_DOES_NOT_EXIST` - The API key does not exist
* `ERROR_IP_NOT_ALLOWED` - IP address is not allowed
* `ERROR_ACCOUNT_DISABLED` - Account is disabled
* `ERROR_INSUFFICIENT_BALANCE` - Insufficient balance

## Best Practices

1. **Keep your API key secret** - Do not expose your API key in public repositories or client-side code.
2. **Use environment variables** - Store your API key in environment variables instead of hardcoding them.
3. **Rotate keys regularly** - Create new API keys periodically and revoke old ones.
4. **Monitor usage** - Regularly check your API usage to detect any suspicious activity.