Webhooks

Webhooks send events to your server as they happen, so you don't have to poll the API.

#Set up

1. More → Developer → APIs → Webhooks.

2. Add a webhook:

   • Endpoint URL: your HTTPS endpoint.
   • HTTP Method: use POST.
   • Signing secret (recommended): used to sign each delivery. See Verify webhook signatures.
   • Event Permissions: the events to receive.
   • Bots to notify: optionally limit chatbot events to certain bots.
   • Active: on.

   

3. Save, then send a test delivery. It carries "_test": true in data.

Webhooks depend on your plan, and only the account owner can manage them.

#Events

#Payload

Every delivery has the same envelope:

{
  "event": "message",
  "action": "incoming",
  "data": {
    "channelType": "whatsapp",
    "from": "+919876543210",
    "text": "Is the 2BHK still available?"
  },
  "timestamp": "2026-10-01T09:30:12.000Z"
}

The data above is an example; its fields vary by event. Send a test delivery to see the exact shape.

For whatsapp events, data carries Meta's original webhook body plus a comms object with Slovio's message ID and status.

#Responding and retries

• Reply with any 2xx within 10 seconds. Do slow work after responding.
• Timeouts, network errors, 408, 429 and 5xx are retried up to 3 attempts in total (after 1 s, then 2 s). Other 4xx responses are not retried.
• After 25 failed deliveries in a row, the webhook is switched off. Fix your endpoint, then switch it back on.
• Each webhook keeps a delivery log. You can replay a delivery from there.

#Common questions

#How fast must my endpoint respond?

Within 10 seconds, with any 2xx status. Save the event and do slow work afterwards, or the delivery times out and is retried.

#Why did my webhook switch itself off?

It failed 25 deliveries in a row. Fix your endpoint, then switch the webhook back on in More → Developer → APIs → Webhooks.

#Are deliveries signed?

Only when you set a Signing secret. Then each delivery carries X-Slovio-Timestamp and X-Slovio-Signature. See Verify webhook signatures.

#Do these webhooks include call events?

No. Call events have their own endpoints under Calling → Webhooks. See Calling webhooks.

#How do I test my endpoint?

Save the webhook and send a test delivery. It carries "_test": true in data, so your code can tell it apart from a real event.