> For the complete documentation index, see [llms.txt](https://docs.wproofreader.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wproofreader.com/v6.12.0/api-reference/user-custom-dictionary-api/errors-reference.md).

# Errors reference

Errors use the standard HTTP API error format.

See [HTTP API Overview](/v6.12.0/api-reference/overview.md#errors) and [HTTP response status codes](/v6.12.0/api-reference/http-response-status-codes.md).

### Error response

Example:

```json
{
  "error": true,
  "is_critical": 0,
  "message": "Failed to add word. Word already exists.",
  "command": "user_dictionary"
}
```

### Error messages

Most failures follow the same structure:

* An **action-level prefix** (what the API tried to do).
* A **detail message** (why it failed).

Example message: "Failed to add word. Word already exists."

### Detail message reference (User Dictionary)

| What happened                                                               | Message                                                                                         | HTTP code |
| --------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------- | --------- |
| Unknown action for this command                                             | Action not found.                                                                               | 404       |
| Dictionary name is missing                                                  | User dictionary name is empty.                                                                  | 400       |
| Dictionary name is too long                                                 | User dictionary name length exceeded. Up to 50 characters allowed.                              | 400       |
| Dictionary name contains forbidden characters                               | Invalid dictionary name. Use Latin letters and digits. No special characters or spaces allowed. | 400       |
| You tried to rename to the same name                                        | The new dictionary name should be different from the existing one.                              | 400       |
| Dictionary already exists                                                   | Dictionary already exists.                                                                      | 400       |
| Word already exists in the dictionary                                       | Word already exists.                                                                            | 400       |
| Word was not found in the dictionary                                        | Word doesn't exist.                                                                             | 404       |
| A required parameter is empty (for example, `word`, `wordlist`, `new_word`) | The '{param}' parameter is empty.                                                               | 400       |
| A word is too long                                                          | Word length exceeded. Up to 63 symbols allowed.                                                 | 400       |
| A word contains forbidden symbols                                           | Invalid word/wordlist. Punctuation, special characters or spaces aren't allowed.                | 400       |
| Dictionary reached maximum size                                             | Dictionary size (50 KB) exceeded. Consider using company-wide dictionary instead.               | 400       |

### Action-level failure prefixes

| Action          | Prefix                             |
| --------------- | ---------------------------------- |
| `create`        | Failed to create dictionary.       |
| `delete`        | Failed to delete dictionary.       |
| `rename`        | Failed to rename dictionary.       |
| `check`         | Failed to check dictionary status. |
| `addword(s)`    | Failed to add word.                |
| `deleteword(s)` | Failed to delete word.             |
| `editword`      | Failed to edit word.               |
| `getdict`       | Failed to get dictionary content.  |
| `setdict`       | Failed to set dictionary.          |

### Notes

#### Validation happens early

The API validates dictionary names and words during request parsing.

It rejects invalid input before running the action.