# Errors

All errors returned by the Tebex Checkout APIs follow the RFC 7807 standard (<https://datatracker.ietf.org/doc/html/rfc7807#section-3.1>).

We also use standardised HTTP response codes to describe each error:

1. **400 Bad Request** - User data validation error
2. **401 / 403 - Authentication / Authorization** (depending on if it's pre- or post- authentication
3. **404** - Requested resource doesn't exist
4. **5xx** - Server side transitory errors.

```javascript
{
  "type": "Not Found",
  "title": "Resource not found",
  "status": 404,
  "detail": "The requested resource does not exist.",
  "instance": "/account/12345"
}
```


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# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.tebex.io/developers/checkout-api/errors.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.