REST API

Prerequisites

To get the most out of this guide, you’ll need to:

Create a project API key in the Kapso dashboard under Integrations → API keys
Connect a WhatsApp number under WhatsApp → Phone numbers

1. Get your credentials

Get your API key and phone number ID from the dashboard.

export KAPSO_API_KEY="your_api_key"
export PHONE_NUMBER_ID="your_phone_number_id"

2. Send a message

The easiest way to send a message is with a simple POST request.

curl

curl -X POST https://api.kapso.ai/meta/whatsapp/${PHONE_NUMBER_ID}/messages \
  -H "X-API-Key: ${KAPSO_API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{
    "messaging_product": "whatsapp",
    "recipient_type": "individual",
    "to": "1234567890",
    "type": "text",
    "text": {
      "preview_url": false,
      "body": "Hello from Kapso!"
    }
  }'

BSUID note

Use to when you have the customer’s phone number. Use recipient when you only have a BSUID or parent BSUID.

{
  "messaging_product": "whatsapp",
  "recipient": "US.13491208655302741918",
  "type": "template",
  "template": {
    "name": "order_update",
    "language": {
      "code": "en_US"
    }
  }
}

Inbound payloads and read surfaces can expose BSUID fields and nullable phone identity. If you also consume webhooks or read message/conversation/contact payloads, see the migration guide:

Business-scoped user IDs

3. Try it yourself

WhatsApp API reference

See all available endpoints.

Getting started

Sending & receiving

Tools & SDKs

Integrations

WhatsApp Flows

FAQs

API Reference

Messages

Usernames

Conversations

Contacts

Calls

Media

Templates

Business Profile

Block Users

Flows

Phone Numbers

Prerequisites

1. Get your credentials

2. Send a message

BSUID note

3. Try it yourself

WhatsApp API reference

​Prerequisites

​1. Get your credentials

​2. Send a message

​BSUID note

​3. Try it yourself

WhatsApp API reference

Prerequisites

1. Get your credentials

2. Send a message

BSUID note

3. Try it yourself