Event Types

Each event has a wire name (the event field in the envelope, e.g. webinar.created) and an enum name used when creating subscriptions (e.g. WEBINAR_CREATED). Subscribe using the enum name; match on the wire name in your receiver. Every event type below is a webinar event. Scheduled studio sessions do not emit webhooks — to track those, use Get Events, which returns sessions and webinars alike.

Wire name	Subscription enum	When it fires
`webinar.created`	`WEBINAR_CREATED`	A webinar is scheduled.
`webinar.started`	`WEBINAR_STARTED`	A webinar goes live.
`webinar.ended`	`WEBINAR_ENDED`	A webinar ends.
`registrant.created`	`REGISTRANT_CREATED`	Someone registers for a webinar.
`attendee.joined`	`ATTENDEE_JOINED`	A registrant joins the live webinar.
`registrant.did_not_attend`	`REGISTRANT_DID_NOT_ATTEND`	A registrant did not attend the webinar.

The payloads below show the data object of the envelope. Test events (fired via sendTestEvent) carry the same shape with an added "test": true marker and obviously synthetic values, so you can build and validate your parser without a real webinar.

Webinar events

webinar.created, webinar.started, and webinar.ended share a common webinar shape. started adds actual_start_time; ended adds actual_end_time and attendee_count.

The webhook payload and Get Events describe the same webinar with different field names: title → name, scheduled_start_time → start_time, scheduled_end_time → end_time. registration_url is the same link on both surfaces.

data (webinar.ended)

{
  "event_id": "sample-webinar-123",
  "id": "sample-webinar-123",
  "title": "Q3 Product Launch Webinar",
  "description": "A live walkthrough of everything shipping this quarter.",
  "scheduled_start_time": "2026-07-15T16:00:00.000Z",
  "scheduled_end_time": "2026-07-15T17:00:00.000Z",
  "timezone": "America/New_York",
  "type": "live",
  "studio_id": "sample-studio-789",
  "studio_slug": "product-webinars",
  "project_id": "sample-project-012",
  "production_id": "sample-production-345",
  "hosted_by": "Ada Lovelace",
  "created_by_user_id": "sample-user-345",
  "registration_url": "https://riverside.fm/webinar/registration/eyJldmVudElkIjoic2FtcGxlLXdlYmluYXItMTIzIiwic2x1ZyI6InByb2R1Y3Qtd2ViaW5hcnMifQ==",
  "actual_start_time": "2026-07-15T16:01:23.000Z",
  "actual_end_time": "2026-07-15T17:04:08.000Z",
  "attendee_count": 142
}

Field	Type	Notes
`event_id`	string	The webinar this event relates to. Equals `id` for webinar events.
`id`	string	The webinar id.
`title`	string \| null	Webinar title.
`description`	string \| null	Webinar description.
`scheduled_start_time`	string \| null	ISO-8601. Planned start.
`scheduled_end_time`	string \| null	ISO-8601. Planned end.
`timezone`	string \| null	IANA timezone the webinar was scheduled in.
`type`	string	Webinar type, e.g. `live`.
`studio_id`	string	The studio hosting the webinar.
`studio_slug`	string \| null	Slug of the hosting studio.
`project_id`	string	Owning project.
`production_id`	string \| null	Owning production.
`hosted_by`	string \| null	Display name of the host.
`created_by_user_id`	string \| null	User who created the webinar.
`registration_url`	string \| null	Public page where an audience member signs up. Points at the pre-registration form when the webinar requires registration, and at the direct-join page (`/webinar/directlink/…`) when it doesn’t. Safe to publish — it is never a per-attendee join link.
`actual_start_time`	string	ISO-8601. Present on `webinar.started` and `webinar.ended`.
`actual_end_time`	string	ISO-8601. Present on `webinar.ended`.
`attendee_count`	integer	Present on `webinar.ended`.

Registrant & attendee events

registrant.created, attendee.joined, and registrant.did_not_attend share a common registrant shape. attendee.joined adds joined_at and sets participated: true; registrant.did_not_attend sets participated: false with a zeroed attendance.

data (attendee.joined)

{
  "event_id": "sample-webinar-123",
  "first_name": "Ada",
  "last_name": "Lovelace",
  "email": "[email protected]",
  "registered_at": "2026-07-01T10:15:30.000Z",
  "approved": true,
  "join_url": "https://riverside.fm/studio/product-webinars?audienceToken=sample-token-abc123",
  "participated": true,
  "joined_at": "2026-07-15T16:03:45.000Z",
  "attendance_rate": null,
  "duration": null,
  "referrer": "https://example.com/landing",
  "utm": {
    "source": "newsletter",
    "medium": "email",
    "campaign": "q3-launch",
    "term": null,
    "content": "header-cta"
  },
  "custom_fields": {
    "Company": "Acme Inc.",
    "Job Title": "Engineering Manager"
  }
}

Field	Type	Notes
`event_id`	string	The webinar this registrant belongs to.
`first_name`	string	Registrant first name.
`last_name`	string \| null	Registrant last name.
`email`	string	Registrant email.
`registered_at`	string	ISO-8601. When they registered.
`approved`	boolean	Whether the registration was approved.
`join_url`	string \| null	Personal join link.
`participated`	boolean	`true` once they join; `false` for no-shows.
`joined_at`	string	ISO-8601. Present on `attendee.joined` only.
`attendance_rate`	number \| null	Fraction of the webinar attended. `0` for no-shows.
`duration`	string \| null	Time attended (`mm:ss`). `"00:00"` for no-shows.
`referrer`	string \| null	Referring URL captured at registration.
`utm`	object \| null	UTM attribution (`source`, `medium`, `campaign`, `term`, `content` — each nullable).
`custom_fields`	object \| null	Custom registration form responses, keyed by field label. Values are a string, boolean, or a phone-number object (`{ countryCode, phoneNumber }`).

Getting Started

Endpoints Reference

Webhooks

Objects Reference

Webinar events

Registrant & attendee events

​Webinar events

​Registrant & attendee events

Webinar events

Registrant & attendee events