Unified Messaging

When you integrate messaging into your application, you typically face a fragmented landscape: one API for SMS, another for WhatsApp, a third for RCS. Each has its own authentication flow, payload format, webhook structure, and delivery logic. Maintaining three parallel integrations means three codebases, three webhook handlers, and three sets of delivery-tracking logic.

EnableX Unified Messaging solves this by providing a single API endpoint that routes your message across SMS, WhatsApp, and RCS. You send one request. EnableX handles channel selection, payload adaptation, fallback orchestration, and unified delivery reporting — all through one integration.

Problems It Solves

Channel Comparison

Each messaging channel has different strengths. Unified Messaging lets you leverage the best of all three without separate integrations:

How It Works

Unified Messaging acts as an intelligent routing layer between your application and the individual messaging channels. Here is the end-to-end flow:

Message Flow

1. You send one API request — POST to /messaging/v1/messages with the recipient number, channel preferences, and channel-specific payloads.
2. EnableX evaluates channels — Based on your preference mode (order, budget, or priority), EnableX determines which channel to attempt first.
3. Message is routed — EnableX adapts your payload to the selected channel's format and dispatches the message.
4. Delivery is attempted — If the first channel succeeds, the cascade stops. If it fails (recipient unreachable on that channel), EnableX automatically falls back to the next channel in the list.
5. Webhook notifications fire — You receive real-time delivery events (queued, sent, delivered, failed, channel-fallback) at your webhook URL.

Preference Modes

The preference field controls how EnableX orders the channels you provide:

Cascade Fallback Logic

When you list multiple channels, EnableX orchestrates delivery as a cascade:

1. The first channel in the resolved order is attempted.
2. If delivery is confirmed (recipient reachable, message accepted by the channel), the cascade stops.
3. If the channel fails (recipient not reachable, channel unavailable, or delivery error), EnableX moves to the next channel automatically.
4. This repeats until the message is delivered or all channels are exhausted.

The cascade decision is based on real-time channel capability detection — not just a timed retry. RCS capability is checked against Google's RCS lookup; WhatsApp reachability is checked via Meta's infrastructure. SMS is universally available and typically serves as the final fallback.

Quick Start

Get a unified message sent in three steps.

Step 1 — Get Your Credentials

In the EnableX Portal, navigate to My Projects → [Your Project] → Overview and note your App ID and App Key. These are the same credentials used across all EnableX messaging APIs.

Step 2 — Send Your First Unified Message

Send a message that tries WhatsApp first, then falls back to SMS:

curl -X POST https://api.enablex.io/messaging/v1/messages \
  -H "Authorization: Basic BASE64(APP_ID:APP_KEY)" \
  -H "Content-Type: application/json" \
  -d '{
  "to": "+919876543210",
  "channels": ["whatsapp", "sms"],
  "preference": "order",
  "whatsapp": {
    "type": "text",
    "recipient_type": "individual",
    "text": {
      "body": "Your order #7821 has shipped. Track at: https://yourapp.com/track/7821"
    }
  },
  "sms": {
    "from": "ENABLEX",
    "data_coding": "plain"
  }
}'

Step 3 — Handle the Response

{
  "code": 200,
  "message": "Message accepted",
  "message_id": "65f1a2b3c4d5e6f7a8b9c0d1"
}

The response confirms acceptance. message_id is your unique identifier — use it to correlate delivery webhooks and poll for status. The actual delivery outcome arrives asynchronously via your webhook URL.

Authentication

The Unified Messaging API uses HTTP Basic Authentication. Every API request must include an Authorization header with your project credentials.

Credentials

Your credentials are available in the EnableX Portal under your project settings:

Authorization Header

Encode APP_ID:APP_KEY as a Base64 string and include it in the header:

POST https://api.enablex.io/messaging/v1/messages
Authorization: Basic BASE64_ENCODED_APP_ID:APP_KEY
Content-Type: application/json

API Host & Base URL

API Host

https://api.enablex.io/messaging/

Version Base URL

https://api.enablex.io/messaging/v1/

The version number (v1) isolates your integration from breaking changes in future releases. All endpoints documented below are relative to this base URL.

Primary Endpoint

https://api.enablex.io/messaging/v1/messages

This single endpoint handles both sending messages and retrieving delivery status (with GET by appending the message_id).

Send Message API

The Send Message API accepts a single POST request that combines channel preferences, delivery mode, and channel-specific payloads. EnableX routes the message across your chosen channels with automatic failover.

Endpoint

Headers

Understanding the Payload Structure

Before looking at the JSON, here is what each part of the payload does:

The Unified Messaging payload has two layers: common fields that apply to every message, and channel-specific objects that define the content for each channel.

Basic Payload

{
  "to": "+919876543210",
  "channels": [
    "whatsapp",
    "sms",
    "rcs"
  ],
  "preference": "order",
  "whatsapp": {
    ...
  },
  "sms": {
    ...
  },
  "rcs": {
    ...
  }
}

Complete Payload Reference

Channel-Specific Payload Details

Each channel object follows the same structure as its individual channel API, with a few exclusions to avoid duplication with the top-level fields:

SMS Object

Follows the SMS API payload. Excluded fields: to, recipient, type, type_details, scheduled_dt, created_dt. Scheduling is not available through Unified Messaging.

{
  "sms": {
    "from": "ENABLEX",
    "data_coding": "plain",
    "template_id": "12345"
  }
}

WhatsApp Object

Follows the WhatsApp Messaging API payload. Excluded fields: to (uses top-level to). Supports template messages, session text, media, and interactive messages.

{
  "whatsapp": {
    "type": "template",
    "template": {
      "name": "order_shipped",
      "language": "en",
      "components": [
        {
          "type": "body",
          "parameters": [
            {
              "type": "text",
              "text": "7821"
            }
          ]
        }
      ]
    }
  }
}

RCS Object

Follows the RCS Messaging API payload. Excluded fields: phone (uses top-level to). Supports text, rich cards, carousels, and suggested actions.

{
  "rcs": {
    "type": "text",
    "agent": "MY_RCS_AGENT",
    "text": "Your order #7821 has shipped.",
    "fallback_text": "Your order #7821 has shipped. Track: https://yourapp.com/track/7821",
    "ttl": 60
  }
}

Send Variations

The Unified Messaging API supports several send modes beyond the basic cascade.

Unified Text Message

When you want to send the same plain text content across all channels (no rich media, no templates), use the unified object instead of providing separate payloads for each channel. This is the simplest possible unified send.

{
  "to": "+919876543210",
  "channels": ["whatsapp", "sms", "rcs"],
  "preference": "order",
  "unified": {
    "body": "Your appointment is confirmed for Monday at 10:30 AM."
  },
  "rcs": {
    "agent": "MY_RCS_AGENT"
  },
  "sms": {
    "from": "CLINICX"
  }
}

The unified.body field sets the text content for all channels. Channel-specific objects (rcs, sms) are still needed for required fields like agent name and sender ID, but you do not need to repeat the message body.

Country-Specific Channel Preferences

Different countries have different channel availability and regulatory requirements. The country_channels object lets you define per-country channel preferences that override the global channels array.

{
  "to": "+919876543210",
  "channels": ["whatsapp", "sms", "rcs"],
  "country_channels": {
    "IN": ["sms", "whatsapp"],
    "US": ["rcs", "sms"]
  },
  "preference": "order",
  "whatsapp": { ... },
  "sms": { ... },
  "rcs": { ... }
}

How it works: EnableX detects the country from the to phone number. If the number matches a country in country_channels, that country's channel array is used. Otherwise, the global channels array applies. The preference mode applies to both global and country-specific arrays.

Parallel Delivery (All Channels Simultaneously)

By default, Unified Messaging uses cascade delivery — try one channel, fall back to the next. If you want the message delivered across all channels at the same time (no failover, just broadcast), set multi_channel_delivery to true.

{
  "to": "+919876543210",
  "channels": ["whatsapp", "sms", "rcs"],
  "multi_channel_delivery": true,
  "whatsapp": { ... },
  "sms": { ... },
  "rcs": { ... }
}

Complete Request Example

This example sends a message that tries WhatsApp first (with a template), then SMS (with sender ID), then RCS (with a rich text and fallback). The preference is order, so channels are tried in the sequence listed:

POST https://api.enablex.io/messaging/v1/messages
Authorization: Basic BASE64(APP_ID:APP_KEY)
Content-Type: application/json

{
  "to": "+919876543210",
  "channels": [
    "whatsapp",
    "sms",
    "rcs"
  ],
  "preference": "order",
  "whatsapp": {
    "type": "text",
    "recipient_type": "individual",
    "text": {
      "body": "Hi there! Your verification code is 847291."
    }
  },
  "sms": {
    "from": "ENABLX",
    "data_coding": "plain",
    "template_id": "99999"
  },
  "rcs": {
    "type": "text",
    "agent": "MY_AGENT",
    "text": "Hi there! Your verification code is 847291.",
    "fallback_text": "Hi there! Your verification code is 847291.",
    "ttl": 60
  }
}

Success Response

{
  "code": 200,
  "message": "Message accepted",
  "message_id": "65f1a2b3c4d5e6f7a8b9c0d1"
}

Channel Routing

Understanding how EnableX selects and routes channels is critical for designing your messaging strategy.

How Channel Selection Works

1. Channel list resolved — EnableX checks if the to number matches any country in country_channels. If yes, that country's channel array is used. Otherwise, the global channels array applies.
2. Preference mode applied — If preference is order, the array order is preserved. If budget or priority, EnableX re-orders channels by cost or performance.
3. Capability check — For the first channel in the resolved order, EnableX performs a real-time capability check:
   • RCS: Checks Google's RCS capability lookup for the recipient's device
   • WhatsApp: Checks recipient reachability via Meta's infrastructure
   • SMS: Universally available — no capability check needed
4. Dispatch or fallback — If the recipient is reachable on the selected channel, the message is dispatched. If not, EnableX moves to the next channel in the list.

Routing Examples

Delivery Status API

Poll for the current delivery status of any message using its message_id.

Endpoint

Request

GET https://api.enablex.io/messaging/v1/messages/65f1a2b3c4d5e6f7a8b9c0d1
Authorization: Basic BASE64(APP_ID:APP_KEY)
Content-Type: application/json

Response

The response includes the overall delivery status and per-channel status objects for every channel that was attempted:

{
  "code": 200,
  "message_id": "65f1a2b3c4d5e6f7a8b9c0d1",
  "to": "+919876543210",
  "channels": ["whatsapp", "sms", "rcs"],
  "preference": "order",
  "delivery": {
    "status": "DELIVERED",
    "channel": "whatsapp",
    "whatsapp": {
      "message_id": "wamid_abc123",
      "status": "DELIVERED",
      "queued": "2026-04-09T10:00:00Z",
      "sent": "2026-04-09T10:00:01Z",
      "delivered": "2026-04-09T10:00:03Z",
      "business_phone": "+6531234567"
    }
  }
}

Delivery Status Values

Per-Channel Status Objects

The delivery object contains a sub-object for each channel that was attempted. Each sub-object includes channel-specific fields:

Error Codes

API Quick Reference

Best Practices

Design Your Channel Order Thoughtfully

Place the richest channel first (RCS or WhatsApp) and SMS last. Rich channels provide better user experience (read receipts, interactive elements), while SMS serves as the universal safety net. A common cascade is: ["rcs", "whatsapp", "sms"].

Always Include Fallback Text for RCS

When sending RCS rich content, include the fallback_text field. This ensures non-RCS devices receive an SMS equivalent automatically, without needing a separate SMS entry in the cascade.

Implement Webhooks for Production

The delivery status API is useful for testing and ad-hoc checks, but always configure a webhook URL for production. Webhooks provide real-time delivery updates without polling overhead.

Store the message_id

Map the message_id from the API response to your internal transaction or order ID. This is your primary key for correlating all delivery events back to the original send.

Use Country-Specific Routing for Regulated Markets

Markets like India (DLT requirements) and the US (10DLC) have channel-specific regulations. Use country_channels to route regulated markets through compliant channels while keeping the richer cascade for other regions.

Use Parallel Mode Sparingly

Parallel delivery (multi_channel_delivery: true) sends across all channels simultaneously. This maximises reach but also maximises cost. Use it only for critical alerts where delivery speed is paramount.

Release Notes

v1.0 — February 24, 2026

Initial release of the Unified Messaging API with support for SMS, WhatsApp, and RCS channels. Delivery mode: order (channels tried in the sequence provided). The budget and priority delivery modes will be introduced in subsequent releases.

What's Next

• Unified Messaging Webhooks — Webhook setup, delivery notification payloads, and handler examples
• SMS Guide — Sender IDs, DLT registration, campaign setup, delivery receipts
• WhatsApp Guide — Template management, interactive messages, media, session messaging
• RCS Guide — Rich cards, carousels, suggested actions, capability check
• Messaging Prerequisites — WABA setup, RCS agent registration, sender ID provisioning