Send your first message in 5 minutes
This guide walks you through creating an API key, listing your conversations, and sending a WhatsApp message via the Watsi API.
Prerequisites
- A Watsi account with a connected WhatsApp Business number
- An existing conversation (send a message to your WhatsApp Business number to create one)
Step 1
Create an API key
Open Settings → API Keys in the Watsi dashboard and click Generate new key. Copy the key immediately — it is shown only once.
Step 2
List your conversations
Verify your key works by fetching conversations. Replace YOUR_API_KEY with the key from Step 1.
curl https://api.watsi.ai/api/v1/conversations \ -H "Authorization: Bearer YOUR_API_KEY"
Response
{
"chats": [
{
"id": "550e8400-e29b-41d4-a716-446655440000",
"customer": {
"name": "Maria Garcia",
"phone": "+5491155551234"
},
"last_message_at": "2025-03-15T10:30:00.000Z",
"status": "open"
}
],
"hasMore": false
}Step 3
Send a message
Pick a conversation ID from the previous response and send a text message. Messages can only be sent within the 24-hour WhatsApp messaging window (since the customer's last inbound message).
curl -X POST https://api.watsi.ai/api/v1/messages \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"conversation_id": "550e8400-e29b-41d4-a716-446655440000",
"body": "Hello from the Watsi API!"
}'Response
{
"message": {
"id": "msg_01HXYZ987654321",
"conversation_id": "550e8400-e29b-41d4-a716-446655440000",
"body": "Hello from the Watsi API!",
"direction": "outbound",
"status": "sent",
"created_at": "2025-03-15T10:35:00.000Z"
}
}Step 4
Check message status
The message status field will update as WhatsApp processes delivery. You can also receive real-time status updates via webhooks.
Next steps
- Authentication guide — learn about API key scopes and security best practices
- API reference — explore all endpoints interactively
- Webhook tutorial — receive events when messages arrive or statuses change
- Pagination & filtering — navigate large result sets efficiently