# Error Response

{% hint style="danger" %}
All Login and Myinfo apps must follow Singpass' [FAPI 2.0-compliant authentication API](https://docs.developer.singpass.gov.sg/docs/technical-specifications/integration-guide) by 31 Dec 2026.

The specifications on this page apply to you only if you are maintaining an existing Login / Myinfo (v5) integration. We encourage you to [migrate](https://docs.developer.singpass.gov.sg/docs/technical-specifications/migration-guides/login-myinfo-v5-apps) early to avoid service disruptions.
{% endhint %}

Singpass APIs are RESTful in design and communicate classes of errors based on the **HTTP status code**. The status code should be used to determine if the error is caused by consumer or provider. Consumers should log the HTTP status code along with the `id` and/or `trace_id` of the error.

<table><thead><tr><th width="191">HTTP Status</th><th>Description</th></tr></thead><tbody><tr><td>4xx</td><td><p>Errors caused by API consumer. You can expect codes such as 400, 401, 403, 404 etc. if incorrect requests are made to APIs.</p><p>Example: <strong>400 Bad Request due to invalid/missing request arguments</strong></p></td></tr><tr><td>5xx</td><td><p>Errors caused by API provider or its dependencies. You can expect codes such as 500, 502, 503 etc if there is an issue on Singpass or its dependencies.</p><p>Example: <strong>500: Internal Server Error due to some kind of programming error.</strong></p></td></tr></tbody></table>

Example: Invalid Request Parameters

```http
HTTP/1.1 400 Bad Request
Connection: keep-alive
Cache-Control: no-cache, no-store, must-revalidate
Transfer-Encoding: chunked
Content-Type: application/json
Date: Thu, 26 Sep 2024 03:36:41 GMT
Content-Length: 190

{
  "id" : "bcba4bc3-534e-4891-bfa2-e872b4502d80",
  "error" : "CLIENT_SIDE_ERROR",
  "error_description" : "This is an invalid request.",
  "trace_id" : "66f4d6c93a23476106150eb7c40d7dc9"
}
```

Example: Server Error

```http
HTTP/1.1 500 Internal Server Error
Cache-Control: no-cache, no-store, must-revalidate
X-XSS-Protection: 0
X-Frame-Options: DENY
Date: Thu, 26 Sep 2024 03:36:41 GMT
Connection: keep-alive
Vary: Origin
Vary: Access-Control-Request-Method
Vary: Access-Control-Request-Headers
X-Content-Type-Options: nosniff
Transfer-Encoding: chunked
Content-Type: application/json
Content-Length: 192

{
  "id" : "bcba4bc3-534e-4891-bfa2-e872b4502d80",
  "error" : "SERVER_SIDE_ERROR",
  "error_description" : "An unexpected error occurred.",
  "trace_id" : "66f4d6c97ef952fbff9f2d20f6b826f9"
}
```

| Path                | Type                             | Description                                                                                                                                                                                                                                                                                               |
| ------------------- | -------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `id`                | `String`                         | The unique identifier for this error/request. Please log this identifier for support and debugging purposes.                                                                                                                                                                                              |
| `trace_id`          | `String InstanceOfAssertFactory` | (Optional) An auxiliary id for request correlation across services. Please also log this identifier for operational support and debugging purposes.                                                                                                                                                       |
| `error`             | `String`                         | Error code representing broad class of error; likely to be one of CLIENT\_SIDE\_ERROR, ARGUMENTS\_NOT\_VALID, SERVER\_SIDE\_ERROR, TOO\_MANY\_REQUESTS. However, specific error codes can be returned for some endpoints, in which case you may find more details in the documentation for that endpoint. |
| `error_description` | `String`                         | Returns human readable general information about the reason for the error. Note that due to security reasons; detailed information is unlikely to be available in this message.                                                                                                                           |