> This page is for version v2025-04-21.
> For other versions, use one of these documentation indexes:
> - v2026-02-09 (default): https://docs.extend.ai/2026-02-09/llms.txt
> - v2025-04-21: https://docs.extend.ai/2025-04-21/llms.txt
> - v2024-12-23: https://docs.extend.ai/2024-12-23/llms.txt

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.extend.ai/llms.txt
> Use this file to discover all available pages before exploring further.
>
> ## API version
> The current API version is `2026-02-09`, served at the site root (no version prefix in URLs).
> If this page URL contains `/2025-04-21/` or `/2024-12-23/`, you are reading an older API version.
> Prefer the current docs at https://docs.extend.ai/llms.txt unless the user explicitly needs that older version.
> Do not treat older-version pages as the source of truth for new integrations.

## Classification Processor Configuration

"Classifiers" categorize documents into predefined types. These can be configured via either the UI or the API.

## Example API Usecases

* **[Create a classifier with a given config](/2025-04-21/developers/api-reference/processor-endpoints/create-processor#request.body.config.ClassificationConfig)** - Set up a new classification processor with your configuration
* **[Update a classifier with a given config](/2025-04-21/developers/api-reference/processor-endpoints/update-processor#request.body.config.ClassificationConfig)** - Modify an existing classifier's configuration
* **[Run an existing classifier with a given config](/2025-04-21/developers/api-reference/processor-endpoints/run-processor#request.body.config.ClassificationConfig)** - Ephemerally execute an existing classifier with a custom configuration that overrides the classifiers's existing settings

## Webhooks

You can consume classification outputs via webhooks, track updates to your classifier, and more. See [Webhook Events](/2025-04-21/product/webhooks/events) for details.

## Configurable Fields

You can view full details of the `ClassificationConfig` in our [API reference](/2025-04-21/developers/api-reference/processor-endpoints/run-processor#request.body.config.ClassificationConfig).

When working with the `ClassificationConfig`, you can configure several key aspects, such as:

* **Prompts** - Custom instructions that guide how the classifier categorizes documents
* **Classifications** - Define the categories and rules for document classification
* **Classifier version** - Specify which version of the classification model to use
* **Advanced options** - Configure context limits, multimodal processing, [page ranges](/2025-04-21/product/page-ranges), and other specialized settings

### Classifier Configuration Example

```typescript
const classificationConfig = {
  type: "CLASSIFY",
  classifications: [
    {
      id: "invoice",
      type: "INVOICE",
      description: "Standard invoice document ...",
    },
    {
      id: "bill_of_lading",
      type: "BILL_OF_LADING",
      description: "Bill of Lading document ...",
    },
  ],
  classificationRules: "- If ...", // Optional custom rules
};
```