The webhook endpoint that receives real-time message activity events from Customer.io. Each event is delivered as an HTTP POST with a JSON payload. Events include a unique delivery ID in the X-CIO-Delivery-ID header for deduplication and tracking.
Triggered when an email message is sent to a recipient.
Content-Type: application/json
email_delivered
Triggered when an email is successfully delivered to the recipient mail server.
Content-Type: application/json
email_opened
Triggered when a recipient opens an email message.
Content-Type: application/json
email_clicked
Triggered when a recipient clicks a link in an email message.
Content-Type: application/json
email_bounced
Triggered when an email bounces due to a permanent or temporary delivery failure.
Content-Type: application/json
email_spammed
Triggered when a recipient marks an email as spam.
Content-Type: application/json
email_dropped
Triggered when an email is dropped and not sent, typically due to the recipient being suppressed or unsubscribed.
Content-Type: application/json
unsubscribed
Triggered when a recipient unsubscribes from messages.
Content-Type: application/json
email_converted
Triggered when a conversion goal is met after sending an email.
Content-Type: application/json
email_failed
Triggered when an email fails to send due to a system error.
Content-Type: application/json
push_sent
Triggered when a push notification is sent to a device.
Content-Type: application/json
push_opened
Triggered when a recipient opens a push notification.
Content-Type: application/json
push_bounced
Triggered when a push notification fails to deliver to the device.
Content-Type: application/json
sms_sent
Triggered when an SMS message is sent.
Content-Type: application/json
sms_delivered
Triggered when an SMS message is successfully delivered.
Content-Type: application/json
sms_failed
Triggered when an SMS message fails to send.
Content-Type: application/json
sms_bounced
Triggered when an SMS message bounces.
Content-Type: application/json
About AsyncAPI
The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.
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