> ## Documentation Index
> Fetch the complete documentation index at: https://developer.omni.z-api.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Connect a channel

> The same code connects all five channels — the SDK detects the type and handles the rest

export const projectName = 'Omni Z-API';

## One piece of code, five channels

You do **not** write one flow per channel. The SDK reads the channel type and dispatches the right flow by itself:

```javascript theme={null}
import OmniZapi from '@omni-zapi/connect';

const client = OmniZapi.newClient({ publicKey: 'YOUR_PUBLIC_KEY' });

// Identical for WhatsApp, WhatsApp Web, Instagram, Messenger and Telegram
const response = await client.connect({ channelId: 'CHANNEL_ID' });

if (response.success) {
  await fetch('/my-backend/connect-channel', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(response),
  });
}
```

The type comes from the channel, not from the call. You set the type in [Create channel](/en/channels/create-channel) and the SDK works out the rest.

## What happens under the hood

<Steps>
  <Step title="The SDK queries the channel">
    It calls [`GET /instances/{channelId}/sdk-info`](/en/channels/sdk-info) to find out the channel type, the matching Meta app and the [allowed origins](/en/channels/sdk-info).
  </Step>

  <Step title="It dispatches the type's flow">
    Each type has its own authorization path — Meta OAuth, QR Code or bot token.
  </Step>

  <Step title="It returns the connection data">
    The returned object changes depending on the channel. See the table below.
  </Step>

  <Step title="You finish on the backend">
    Send the result to [`POST /v1/channels/{channelId}/connect`](/en/channels/connect-channel) using the Secret Key.
  </Step>
</Steps>

## Authorization flow per channel

| Channel               | How it authorizes               | Page                                       |
| --------------------- | ------------------------------- | ------------------------------------------ |
| **WhatsApp Official** | Meta Embedded Signup            | [Meta WhatsApp](/en/connect/meta-whatsapp) |
| **WhatsApp Web**      | QR Code                         | [WhatsApp Web](/en/connect/whatsapp-web)   |
| **Instagram**         | Instagram OAuth                 | [Instagram](/en/connect/instagram)         |
| **Messenger**         | Facebook OAuth + page selection | [Messenger](/en/connect/messenger)         |
| **Telegram**          | Bot token                       | [Telegram](/en/connect/telegram)           |

## The response changes per channel

All of them return `success` and `channelId`. The rest depends on the type:

| Field         | WhatsApp Official | WhatsApp Web | Instagram | Messenger | Telegram |
| ------------- | :---------------: | :----------: | :-------: | :-------: | :------: |
| `code`        |         ✅         |       —      |     ✅     |     ✅     |     —    |
| `wabaId`      |         ✅         |       —      |     —     |     —     |     —    |
| `phoneId`     |         ✅         |       —      |     —     |     —     |     —    |
| `coexistence` |         ✅         |       —      |     —     |     —     |     —    |
| `accessToken` |         —         |       —      |     ✅     |     ✅     |     —    |
| `pageId`      |         —         |       —      |     —     |     ✅     |     —    |
| `botToken`    |         —         |       —      |     —     |     —     |     ✅    |

<Note>
  Do not handle these fields manually. Send the whole object to your backend and forward it as-is to the connect endpoint — it knows what to do with each type.
</Note>

<Warning>
  Connecting only works from allowed domains, and the SDK fails silently when the origin is not on the list. Read [SDK origins](/en/channels/sdk-info) before integrating.
</Warning>

## Without the SDK

The SDK exists because each channel has a different authorization flow on its source platform, and all of them need a browser window. If you need to build this by hand, each channel page describes the authorization URL, the scopes and the parameters used.