> ## Documentation Index
> Fetch the complete documentation index at: https://onextel-09023014.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# OmniChannel API Overview

> Send SMS, RCS, and WhatsApp messages — with automatic fallback — through a single OneXtel API endpoint.

The OmniChannel Send API is a single endpoint that spans all three OneXtel messaging
channels — **SMS**, **RCS**, and **WhatsApp** — plus an optional automatic fallback
mechanism between channels. Instead of integrating separately with each channel's send
API, you can call one endpoint and route messages across channels from a single
request payload.

## Base URL

```
https://api.onexaura.com
```

## Authentication

Every request is authenticated with an `apikey` header carrying the API key issued to
your OneXtel account.

<ParamField header="apikey" type="string" required>
  API key issued by OneXtel, used for authentication.
</ParamField>

## The send endpoint

```
POST https://api.onexaura.com/oapi/send_sms
```

Despite the `send_sms` path, this single endpoint accepts payloads for SMS, RCS, and
WhatsApp — the channel is determined by which top-level key (`sms`, `wa`, or `rcs`) you
include in the request body. Adding a `fallback` object to the same request enables
automatic fallback to a secondary channel if the primary channel doesn't deliver within
a configured wait time.

## What's in this section

| Page | Covers |
| - | - |
| [Fallback API](/api-reference/omnichannel/fallback) | Sending on a primary channel with automatic fallback to one or more secondary channels in a single call to `/oapi/send_sms`. |
| [Message Status](/api-reference/omnichannel/message-status) | Looking up delivery status for one or more messages by message ID (or mobile number) across channels. |
| [Message History](/api-reference/omnichannel/message-history) | Querying historical message records with filters for channel, duration, status, and message type. |

## Per-channel API references

For channel-specific send APIs (templates, media, non-template messages, opt-in/opt-out,
etc.), see the dedicated API reference for each channel:

| Channel | Reference |
| - | - |
| WhatsApp | [/api-reference/whatsapp/overview](/api-reference/whatsapp/overview) |
| RCS | [/api-reference/rcs/overview](/api-reference/rcs/overview) |
| SMS | [/api-reference/sms/overview](/api-reference/sms/overview) |

<Tip>
  Use the channel-specific references when you need channel-only sends (no fallback), and
  the OmniChannel Send API when you want fallback across channels in a single request.
</Tip>


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