# Custom errors

Custom errors can be used in the manual intervention module to indicate certain errors where you want to perform certain actions. A custom defined problem consists of a code and a message. You can choose between document classification and entity extraction errors. When using the custom error codes in manual intervention when marking a document as failed, Metamaze will send these codes and messages to your service.

![](/files/KVzLjJzdwaO0ca1wEMSE)


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

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

```
GET https://docs-old.app.metamaze.eu/project/project-settings/custom-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.