Developers

REST API

Connect WhatsApp messaging to your app with a few HTTP requests. Authentication uses the instance API key.

REQUEST

POST /api/{instanceId}/send
Content-Type: application/json
X-API-Key: API_KEY

{
  "phone": "+905551234567",
  "message": "Hello"
}

RESPONSE

{
  "success": true,
  "instanceId": "example-instance",
  "messageId": "example-message-id",
  "quotaRemaining": "unlimited"
}

Base URL

https://app.kolaywhatsapp.com

Message, QR, and status endpoints require X-API-Key — generated with the instance, rotatable in the panel.

Instance creation endpoints require a separate server secret (external integration).

Code	Meaning
200	Sent
400	Missing phone or message
401	Invalid or missing API key
403	Premium required or quota exhausted
503	WhatsApp connection not ready
500	Server error

WhatsApp message.received KolayWhatsApp POST webhook Your system 200 OK

When a webhook secret is set, delivery is signed with HMAC-SHA256.

Customer
Can I speak with someone?

Assistant
Sure, connecting you to the team. Chatbot

Agent took over

Sample flow — design branches with message and condition nodes in the chatbot builder.

POST /api/{instanceId}/send
Text message. Body: phone, message. Non-premium instances consume credits.
POST /api/{instanceId}/send-media
Media upload. multipart file field.
GET /api/{instanceId}/qr-code
Connection QR when status is qr_code_generated.
GET /api/{instanceId}/status
initializing | qr_code_generated | connected | disconnected | requires_premium
POST /api/instances/create
External provisioning. X-API-Secret. First instance gets 30 days premium.