📱 1. Linking Your WhatsApp (QR Code Scanner)

NextGen WhatsApp operates as a sovereign, multi-device companion client. Your WhatsApp account stays securely in your control on your primary phone.

How to Link Your WhatsApp Device:

1. Open WhatsApp on your mobile phone.
2. Navigate to Settings (or 3 dots menu on Android) ➔ Linked Devices.
3. Tap "Link a Device" (authenticate via fingerprint/FaceID).
4. Point your camera at the live QR code shown on the screen.
5. Within 5–10 seconds, your screen will turn green showing 🟢 Connected and display your phone number.

💡 Need to switch numbers? Click "🔄 Relink Device" anytime to revoke the active session and generate a fresh QR code.

✍️ 2. Message Composer (Text, Media & Polls)

The Message Composer enables you to dispatch clean, professional messages directly from your linked phone number to any valid recipient or community group.

Supported Message Types:

• Text Messages: Supports WhatsApp bold (*bold*), italics (_italic_), strikethrough (~strike~), and emojis.
• Images & Photos: High-resolution image attachments with accompanying captions.
• PDF & Documents: Invoices, maintenance bills, and notices delivered directly with file names.
• Interactive Polls: Create decision polls with 2 to 12 selectable options and single or multiple choice toggles.

⏰ 3. Offline Scheduled Queue (Close Your Laptop)

The defining power of the NextGen Studio is unattended offline execution. Once scheduled, our resilient background daemon executes the dispatch at the exact minute specified.

How Scheduling Works:

1. In the Message Composer, toggle the "📅 Schedule for Later" switch.
2. Select the target dispatch date and time.
3. Click "Schedule Message".
4. Visit the Queue Manager tab anytime to view pending dispatches, edit scheduled times, or cancel dispatches.

🤖 4. Keyword Auto-Replies & Spreadsheet Lookup

Turn your WhatsApp into an intelligent 24/7 automated receptionist that answers frequent questions instantly.

Types of Automated Responses:

• Static Keyword Triggers: When an incoming message contains words like "office hours", "timing", or "helpline", the bot automatically replies with pre-configured directory details.
• Dynamic Spreadsheet Data Lookup: Upload an Excel or CSV file (e.g., flat resident directory, test results, or inventory). When a user messages their Flat Number or Order ID, the system looks up the matching row and replies with live details.
• Group Scoping: Configure rules to reply exclusively inside individual direct messages or in specific joined groups.

🛡️ 5. Anti-Spam Safety & Meta Compliance Rules

WhatsApp strictly monitors accounts for robotic burst behavior. To ensure 100% account longevity and zero risk of suspension, NextGen enforces built-in safety mechanisms:

• Rolling Hourly Quota: Accounts are configured with safe rolling limits (default: 10 to 50 messages/hour).
• Automatic Backoff: If rate limits are approached, pending scheduled items automatically stagger themselves rather than dropping.
• Anti-Spam Verification: WhatsApp pre-keys and cryptographic ratchets are maintained with graceful reconnection to avoid session corruption.

🔒 6. DPDP 2023 & HIPAA Zero-Storage Compliance

India's Digital Personal Data Protection Act (DPDP 2023) and healthcare guidelines require strict data minimization.

• Zero Cloud Message Storage: Message text, recipient phone lists, and attachments are dispatched through the WhatsApp protocol in transit and never retained on permanent cloud servers.
• Client-Side Decryption: Your WhatsApp session cryptographic keys reside solely inside your sandboxed user directory.
• User Privacy Modes: Configurable in your Account & Privacy tab between Standard Zero-Storage and User-Encrypted audit logs.

⚡ 1. API Base URL & Authentication

All REST API endpoints require HTTPS and must be authenticated using your dedicated API Key issued in the API Keys & Tenants dashboard.

Supported Authentication Headers:

You can pass your API key via either header:

• x-api-key: mhc_sec_YOUR_API_KEY
• Authorization: Bearer mhc_sec_YOUR_API_KEY

🎯 2. WhatsApp Recipient Standards (JIDs)

The gateway automatically sanitizes recipient identifiers, but adhering to WhatsApp standards ensures optimal delivery:

📤 3. POST /api/v1/send-message

Dispatches text, media, documents, or interactive polls to individuals or groups.

curl -X POST https://dev-wa.nextgenmultiverse.com/api/v1/send-message \
  -H "Content-Type: application/json" \
  -H "x-api-key: mhc_sec_demo_app_998877" \
  -d '{
    "to": "919013793020",
    "type": "text",
    "text": "Hello! Your verification code is 481923."
  }'

curl -X POST https://dev-wa.nextgenmultiverse.com/api/v1/send-message \
  -H "Content-Type: application/json" \
  -H "x-api-key: mhc_sec_demo_app_998877" \
  -d '{
    "to": "12036304859182394@g.us",
    "type": "document",
    "mediaUrl": "https://example.com/monthly-bill.pdf",
    "fileName": "RWA-Invoice-Sept.pdf",
    "caption": "Attached is the society maintenance invoice."
  }'

Success Response (HTTP 200):

{
  "success": true,
  "messageId": "BAE5F928C1A4B02E",
  "timestamp": 1726762800000,
  "sourceApp": "rwa-portal"
}

👥 4. GET /api/v1/groups

Fetches all WhatsApp groups that the sender channel is currently participating in.

curl -X GET https://dev-wa.nextgenmultiverse.com/api/v1/groups \
  -H "x-api-key: mhc_sec_demo_app_998877"

🩺 5. GET /api/v1/health

Real-time gateway connectivity status and socket health verification.

curl -X GET https://dev-wa.nextgenmultiverse.com/api/v1/health \
  -H "x-api-key: mhc_sec_demo_app_998877"

🔌 6. Client Webhooks & Real-time Receipts

External applications can receive instant HTTP POST webhooks for incoming replies and delivery receipts.

Payload Signature Verification:

Each webhook request includes an x-hub-signature-256 header containing the HMAC-SHA256 hash of the payload signed with your webhook secret.

⚠️ 7. Rate Limits & HTTP Error Codes

💻 8. Multi-Language SDK Samples

Node.js (Axios)

const axios = require('axios');

async function sendWhatsAppMessage() {
  try {
    const res = await axios.post('https://dev-wa.nextgenmultiverse.com/api/v1/send-message', {
      to: '919013793020',
      type: 'text',
      text: 'Hello from Node.js backend!'
    }, {
      headers: {
        'Content-Type': 'application/json',
        'x-api-key': 'mhc_sec_demo_app_998877'
      }
    });
    console.log('Dispatched successfully:', res.data.messageId);
  } catch (error) {
    console.error('API Error:', error.response ? error.response.data : error.message);
  }
}
sendWhatsAppMessage();

Python (Requests)

import requests

url = "https://dev-wa.nextgenmultiverse.com/api/v1/send-message"
headers = {
    "Content-Type": "application/json",
    "x-api-key": "mhc_sec_demo_app_998877"
}
payload = {
    "to": "919013793020",
    "type": "text",
    "text": "Hello from Python backend service!"
}

response = requests.post(url, json=payload, headers=headers)
print("Status:", response.status_code)
print("Response:", response.json())

PHP (cURL)

<?php
$payload = json_encode([
  'to' => '919013793020',
  'type' => 'text',
  'text' => 'Hello from PHP microservice!'
]);

$ch = curl_init('https://dev-wa.nextgenmultiverse.com/api/v1/send-message');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
  'Content-Type: application/json',
  'x-api-key: mhc_sec_demo_app_998877'
]);

$response = curl_exec($ch);
curl_close($ch);
echo $response;
?>