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updatedAt: 2026-06-29T16:41:39.000Z
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# API status codes and errors

The Search Engine Marketing (SEM) APIs return standard HTTP status codes to indicate whether a request was successful or failed.

Most error responses include:

* an HTTP status code,
* a machine-readable error code,
* and a human-readable error description to help identify and troubleshoot issues.

## Common HTTP status codes

| HTTP status                 | Description                                          | Common causes                                                            |
| --------------------------- | ---------------------------------------------------- | ------------------------------------------------------------------------ |
| `200 OK`                    | Request completed successfully                       | Successful retrieval or update                                           |
| `204 No Content`            | Request completed successfully with no response body | Successful delete or stop operations                                     |
| `400 Bad Request`           | Invalid request parameters or malformed request body | Invalid filters, invalid date ranges, malformed JSON, unsupported values |
| `401 Unauthorized`          | Authentication failed                                | Missing, invalid, or expired access token                                |
| `403 Forbidden`             | Access denied                                        | Seller does not have permission to access the requested SEM feature      |
| `404 Not Found`             | Requested resource not found                         | Invalid campaign ID or missing resource                                  |
| `422 Unprocessable Entity`  | Request payload validation failed                    | Invalid request structure or unsupported content type                    |
| `429 Too Many Requests`     | Rate limit exceeded                                  | Too many requests sent within the allowed time window                    |
| `500 Internal Server Error` | Unexpected server-side error                         | Temporary service or processing issue                                    |
| `503 Service Unavailable`   | Service temporarily unavailable                      | Temporary outage or maintenance window                                   |

## Error response structure

Most SEM APIs return structured error responses containing:

* `code`: Machine-readable error identifier
* `description`: Human-readable error message
* `info`: Additional context about the error
* `severity`: Error severity level
* `category`: Error classification

Example:

```json
{
  "error": [
    {
      "code": "INVALID_REQUEST.SEM_API",
      "description": "Request not valid",
      "info": "End date cannot be before start date",
      "severity": "Error",
      "category": "Data specific error"
    }
  ]
}
```

## Rate limiting

SEM APIs enforce request rate limits to ensure platform stability.

If you submit too many requests in a short period of time, you may exceed Walmart’s rate limits and receive HTTP 429 (Too Many Requests) responses. For more details on throttling and best practices, refer to the <Anchor target="_blank" href="/us-marketplace/docs/rate-limiting">Rate Limiting Guide</Anchor>.