---
id: i8AhTf8UVKZz
title: Start Your Cloud Communication
url: overview
description: Explore MSG91 APIs and developer tools to build OTP verification, transactional messaging, multi-channel campaigns, and automated workflows across SMS, WhatsApp, Email, and Voice. Includes API references, SDKs, integrations, and CLI tools.
type: 1
updated_at: '2026-10-05T08:42:17.754Z'
---

## MSG91 API Documentation

## Build powerful communication experiences with MSG91

MSG91 is a cloud communication platform that helps you connect with your users across **SMS, WhatsApp, Email, and Voice**.

Use MSG91 APIs and developer tools to build **OTP verification, transactional messaging, notifications, campaigns, customer communication, and automated workflows**.

**\[Get Started\]** · [**Login / Sign Up**](https://control.msg91.com/signin/)

* * *

## 🚀 Get Started

Choose what you want to build:

Use case

Recommended solution

🔐 **User verification & OTP**

OTP APIs / OTP Widget

📱 **Send SMS**

SMS API

💬 **Send WhatsApp messages**

WhatsApp API

📧 **Send Emails**

Email API

📞 **Make Voice calls**

Voice API

📢 **Multi-channel communication**

Campaign API

👥 **Manage contacts & segments**

Segmento

* * *

## I. Configure Your Communication Channel

Before using an API, configure the communication channel you want to use.

## 📱 SMS

Configure your **Sender ID, DLT registration, templates, and SMS settings** before sending messages.

[**Configure SMS →**](https://msg91.com/help/MSG91/step-by-step-process-to-configure-sms)

* * *

## 💬 WhatsApp

Complete the required Meta/WhatsApp setup, connect your WhatsApp Business Account, and sync your templates with MSG91.

[**Configure WhatsApp →**](https://msg91.com/help/MSG91/guide-to-whatsapp-messaging-with-msg91)

[**Get Started with WhatsApp →**](https://msg91.com/help/MSG91/how-to-begin-with-whatsapp)

* * *

## 📧 Email

Configure your sending domain and complete the required authentication before sending emails through the API.

[**Configure Email →**](https://msg91.com/help/MSG91/step-by-step-process-to-configure-email-api-in-msg91)

* * *

## 📞 Voice

Configure your Voice services, templates, and calling setup.

[**Configure Voice →**](https://msg91.com/help/how-to-use-voice-services)

> Need help with configuration? [**Contact MSG91 Technical Support**](https://calendly.com/support--msg91)

* * *

## II. Choose Your API

Once your communication channel is configured, select the API that matches your use case.

## 🔐 OTP & Authentication

Build secure login and user verification flows using OTP.

*   **Send OTP** — [API Reference](https://docs.msg91.com/otp/sendotp)
    
*   **Resend OTP** — [API Reference](https://docs.msg91.com/otp/resend-otp)
    
*   **Verify OTP** — [API Reference](https://docs.msg91.com/otp/verify-otp)
    
*   **OTP Widget** — [Integration Guide](https://msg91.com/help/MSG91/how-to-integrate-the-new-login-with-otp-widget)
    

You can use the OTP APIs individually or integrate the OTP Widget to manage the complete OTP flow.

* * *

## 📱 SMS

Send transactional and promotional SMS through the MSG91 API.

[**Send SMS API →**](https://docs.msg91.com/sms/send-sms)

* * *

## 💬 WhatsApp

Send WhatsApp template messages and other supported WhatsApp communications through MSG91.

[**WhatsApp API Reference →**](https://docs.msg91.com/whatsapp/template-bulk)

* * *

## 📧 Email

Send emails programmatically through MSG91.

[**Send Email API →**](https://docs.msg91.com/email/send-email)

* * *

## 📢 Multi-Channel Messaging

Use the Campaign API to manage communication across multiple supported channels through a unified API.

[**Campaign API / Help Guide →**](https://msg91.com/help/what-is-campaign-and-how-to-use-it)

**Recommended** when you want to manage communication across channels without integrating each channel separately.

* * *

## III. Explore MSG91 Services

MSG91 provides additional tools to help you manage and automate your communication workflows.

## 💬 Hello

A customer communication platform for **Tickets, Live Chat, Bot, and Help Centre**.

Use Hello to:

*   Manage customer support tickets
    
*   Facilitate live chat
    
*   Create internal teams
    
*   Connect with customers through calls or screen sharing
    
*   Create and publish Help Centre articles
    

[**Explore Hello →**](https://msg91.com/help/MSG91/what-is-hello)

* * *

## 👥 Segmento

A contact management and campaign platform that helps you manage customer data and create targeted communication campaigns.

With Segmento, you can:

*   Import existing users using CSV
    
*   Add users and attributes through APIs
    
*   Create customer segments
    
*   Send SMS, WhatsApp, Email, and other supported communications
    
*   Automate campaigns based on customer segments and events
    

[**Explore Segmento →**](https://msg91.com/help/MSG91/what-is-segmento-and-how-to-send-emails-using-it)

* * *

## IV. API Reference

Explore detailed API documentation including endpoints, parameters, authentication, request examples, and responses.

### Communication APIs

*   **SMS** — [Explore SMS APIs](https://docs.msg91.com/sms/send-sms)
    
*   **WhatsApp** — [Explore WhatsApp APIs](https://docs.msg91.com/whatsapp/template-bulk)
    
*   **Email** — [Explore Email APIs](https://docs.msg91.com/email/send-email)
    
*   **OTP** — [Explore OTP APIs](https://docs.msg91.com/otp/sendotp)
    

* * *

## V. SDKs & Integrations

Integrate MSG91 into your applications using our available SDKs and platform integrations.

## Mobile SDKs

*   **iOS** — [GitHub](https://github.com/MSG91/sendotp-ios)
    
*   **Android** — [GitHub](https://github.com/walkovermsg91/sendotp-android)
    

## Plugins & Integrations

MSG91 provides integrations and plugins for platforms and frameworks such as **WordPress, Magento, and WHMCS**.

[**Explore Integrations →**](https://msg91.com/partners-and-integrations/)

* * *

## VI. Developer Resources

Resource

Description

**API Reference**

Explore endpoints, parameters, requests, and responses

**Help Center**

Find product setup and configuration guides

**SDKs**

Integrate MSG91 into your applications

**Integrations**

Connect MSG91 with popular platforms

**Technical Support**

Get assistance with configuration and API-related issues

* * *

## VII. Run MSG91 APIs from Your Terminal

DocStar provides a dedicated CLI for `docs.msg91.com`, allowing developers to **discover and run published MSG91 APIs directly from the terminal**.

## Install the CLI

Copy

```
npm i -g docstar-editor
```

## Initialize MSG91 APIs

Copy

```
docstar-editor init docs.msg91.com
```

The CLI follows the structure:

**Collection → Module → Endpoint**

For example:

Copy

```
MSG91
 └── WhatsApp
      └── Send Template Message
```

You can then run an API directly from your terminal:

Copy

```
docstar-editor msg91 whatsapp send-template-message \
  --to "919876543210" \
  --template "welcome"
```

The CLI uses the published API contract and prompts you for required parameters when needed.

* * *

## VIII. Connect MSG91 APIs with AI Clients

You can expose your installed MSG91 APIs as **MCP tools** for compatible AI clients such as Claude.

Run:

Copy

```
docstar-editor mcp
```

This enables AI clients to **discover and call installed MSG91 APIs directly**, without manually navigating through the documentation.

### With the DocStar CLI, you can:

*   Discover published MSG91 APIs
    
*   Install required API modules
    
*   Run APIs directly from your terminal
    
*   Get prompted for required parameters
    
*   Expose installed APIs as MCP tools
    
*   Allow compatible AI clients to discover and call MSG91 APIs
    

* * *

## 🔑 Ready to get started?

Start building with MSG91 APIs today.

[**Login / Sign Up →**](https://control.msg91.com/signin/)