> ## Documentation Index > Fetch the complete documentation index at: https://docs.riverside.fm/llms.txt > Use this file to discover all available pages before exploring further. # Event Types > The catalog of webhook events you can subscribe to, and the payload each one delivers. Each event has a **wire name** (the `event` field in the [envelope](/webhooks/overview#the-event-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. | 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](/webhooks/overview#the-event-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`. ```json data (webinar.ended) theme={null} { "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", "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. | | `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. ```json data (attendee.joined) theme={null} { "event_id": "sample-webinar-123", "first_name": "Ada", "last_name": "Lovelace", "email": "ada@example.com", "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 }`). |