# Transformers Overview

**Cognigy Support**  
January 28, 2026

A basic understanding of [JavaScript](https://developer.mozilla.org/en-US/docs/Web/JavaScript) is recommended when using transformer functions.

With the help of [Transformers](https://docs.cognigy.com/docs/transformers), one can customize and manipulate the behavior of the NLU of an Endpoint.

> [Watch Cognigy Sessions Episode "Endpoint Transformers" for a technical deep dive](https://support.cognigy.com/hc/en-us/articles/360019893159-Cognigy-Sessions-Endpoint-Transformers)

In general, a transformer function is used for manipulating incoming or outgoing messages. With this functionality, one could, for example, translate a text or transform the Cognigy.AI message output in order to fit a specific format.  In order to share this knowledge, the following table consists of free-to-use examples.

_Please note that Cognigy does not provide enterprise support for developed Transformers. This repository is [licensed under MIT,](https://github.com/Cognigy/WebchatPlugins/blob/master/LICENSE)  in which the community is responsible for the shared code._

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# Library

There are two different types of transformer functions, namely **Endpoint** and **NLU**.

## Endpoint Transformers

| Icon | Name | Description | Type | Download | Version |
| --- | --- | --- | --- | --- | --- |
|  | [Avaya Voice Channel](https://github.com/Cognigy/Transformers/tree/master/endpoint/avayaVoiceChannel) | Use the Avaya Voice Channel | REST | [Download](https://github.com/Cognigy/Transformers/releases/download/avayavoicechannel112/transformer.ts) | 1.1.2 |
|  | [Realtime Translation](https://github.com/Cognigy/Transformers/tree/master/endpoint/webchat/translate) | Translate messages automatically with Microsoft, Google Translate or DeepL | Webchat | [Download](https://github.com/Cognigy/Transformers/releases/download/realtimeTranslation130/transformer.ts) | 1.3.0 |
|  | [Telegram](https://github.com/Cognigy/Transformers/tree/master/endpoint/webhook/telegram) | Connect to the Telegram Messenger _(4.1.5 and higher!)_ | Webhook | [Download](https://github.com/Cognigy/Transformers/releases/download/telegram100/transformer.ts) | 1.0.0 |
|  | [Tyntec - WhatsApp](https://github.com/Cognigy/Transformers/tree/master/endpoint/webhook/tyntec-whatsapp) | Deploy a virtual agent on WhatsApp | Webhook | [Download](https://github.com/Cognigy/Transformers/releases/download/tyntecWhatsAppWebhook110/transformer.ts) | 1.1.0 |
|  | [Vonage - WhatsApp](https://github.com/Cognigy/Transformers/tree/master/endpoint/webhook/vonage-whatsapp) | Deploy a virtual agent on WhatsApp | Webhook | [Download](https://github.com/Cognigy/Transformers/releases/download/vonage-whatsapp10/transformer.ts) | 1.0.0 |
|  | [LEKAB Rich API](https://github.com/Cognigy/Transformers/tree/master/endpoint/webhook/lekabapi) | Connect to the LEKAB Rich API | Webhook | [Download](https://github.com/Cognigy/Transformers/releases/download/lekab100/transformer.ts) | 1.0.0 |

## NLU Transformers

| Icon | Name | Description | Download | Version |
| --- | --- | --- | --- | --- |
|  | [Rasa](https://github.com/Cognigy/Transformers/blob/master/nlu-connector/rasa) | Use the Rasa NLU | [Download](https://github.com/Cognigy/Transformers/releases/download/rasa100/transformer.ts) | 1.0.0 |

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## How to's & Tutorials

- [Installation](https://support.cognigy.com/hc/en-us/articles/360019665180)
- [Concepts](https://support.cognigy.com/hc/en-us/articles/360019665060)
- [How to use the Session Storage as Context in an Endpoint Transformer Function](https://support.cognigy.com/hc/en-us/articles/360019586819)

### Transformers

- [Transformers Overview](https://support.cognigy.com/hc/en-us/articles/360019704899-Transformers-Overview)
- [Transformers Installation](https://support.cognigy.com/hc/en-us/articles/360019665180-Transformers-Installation)
- [Transformer - Logging, Session Timeout, Hiding User and SessionId](https://support.cognigy.com/hc/en-us/articles/360019665060-Transformer-Logging-Session-Timeout-Hiding-User-and-SessionId)
- [How to use the Session Storage as Context in an Endpoint Transformer Function](https://support.cognigy.com/hc/en-us/articles/360019586819-How-to-use-the-Session-Storage-as-Context-in-an-Endpoint-Transformer-Function)