Events & Payloads

This page covers the different types of webhook events you can subscribe to and the structure of the data we send to your endpoint.

Available Events

domain.flagged.disposable

Triggers when a new domain is flagged as disposable in our systems and you've previously made requests for it using an API key that matches your webhook's environment within the last 30 days.

This is useful for updating your local cache or taking immediate action when a domain you've previously validated becomes flagged as disposable.

domain.flagged.relay

Same as above, but for relay domains.

domain.flagged.spam

Same as above, but for spam domains.

Webhook Payload

When an event occurs, we'll send a POST request to your webhook endpoint with the following structure:

Example Payloads

{
  "event": "domain.flagged.disposable",
  "created_at": "2025-03-26T14:30:25+00:00",
  "data": {
    "domain": "example.com"
  }
}

Payload Fields

Field	Type	Description
event	string	The type of event that occurred
created_at	string	ISO 8601 timestamp of when the event occurred
data	object	Event-specific data containing relevant information

Request Headers

When we send a webhook to your endpoint, the request includes several helpful headers:

Header	Description
X-UserCheck-Signature	HMAC SHA-256 signature for verification
X-UserCheck-Event-Type	The event type (e.g., domain.flagged.disposable)
X-UserCheck-Delivery-ID	Unique identifier for this delivery attempt
X-UserCheck-Attempt	Current attempt number