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

# Error & success codes

> Response shapes and error codes for the Atelerix REST API.

## Success response

A successful request returns HTTP `200` or `201` with a JSON body:

```json theme={null}
{
  "success": true,
  "message": "Notification sent successfully"
}
```

## Error response shape

Most errors return:

```json theme={null}
{
  "message": "This Project Not Founded",
  "error": "PROJECT_NOT_FOUND",
  "statusCode": 400
}
```

`error` is a stable, machine-readable code you can safely match on. `message` is
a human-readable description and may change wording over time — don't parse it.

<Note>
  A few less common failure paths (like exceeding your plan's notification
  limit, or a resolved device token/key not being found) throw a generic Nest
  exception instead of a coded one. For those, `error` falls back to the
  generic HTTP reason phrase (e.g. `"Bad Request"`, `"Not Found"`) rather than
  a specific code — check the HTTP status and `message` text in that case.
</Note>

## Common error codes

| HTTP status | `error`                                | Meaning                                                                                                                           |
| ----------- | -------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------- |
| 400         | `PROJECT_NOT_FOUND`                    | `projectSlug` doesn't match any project                                                                                           |
| 400         | `DONT_HAVE_ACCSESS_PROJECT`            | The authenticated identity doesn't have access to this project                                                                    |
| 404         | `API_KEY_NOT_VALID`                    | `apiKey` doesn't match any key on this project                                                                                    |
| 400         | `PROJECT_API_KEY_DONT_HAVE_PERMISSION` | The API key exists but isn't granted the permission this endpoint needs (e.g. Send Push Notifications)                            |
| 404         | `TOPIC_NOT_FOUND`                      | `sendByTopic` was `true` but no topic matches `topic` for this project                                                            |
| 400         | *(generic — "Bad Request")*            | Notification limit reached for your plan                                                                                          |
| 404         | *(generic — "Not Found")*              | None of the given `deviceTokens` matched a registered device                                                                      |
| 400         | *(generic — "Bad Request")*            | A device resolved to iOS, but no Apple push key is configured for this project yet — upload one from **Notifications → Settings** |
| 404         | `NOTIFICATION_NOT_FOUND`               | `notificationId` (the `{id}` path parameter) doesn't match any notification for this API key's project                            |
| 404         | `SCHEDULED_NOTIFICATION_NOT_FOUND`     | Same as `NOTIFICATION_NOT_FOUND`, returned by [Cancel a scheduled notification](/api-reference/cancel-notification)               |
| 400         | `CANNOT_CANCEL_SENT_NOTIFICATION`      | [Cancel](/api-reference/cancel-notification) was called on a notification that isn't `scheduled` anymore                          |
| 400         | `CANNOT_UPDATE_CANCELED_NOTIFICATION`  | [Update](/api-reference/update-notification) was called on a `canceled` notification                                              |
| 400         | `CANNOT_UNSEND_NOTIFICATION`           | [Unsend](/api-reference/unsend-notification) was called on a notification whose status isn't `sent`                               |

## Validation errors

Missing or malformed required fields (e.g. an empty `title`) return `400` with
a `message` array describing each failing field, in the standard NestJS
validation-pipe shape:

```json theme={null}
{
  "message": ["title should not be empty"],
  "error": "Bad Request",
  "statusCode": 400
}
```