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Use cases → Scheduling

Send event invites to an entire organisation with delegation

Add all users in a Workspace domain as attendees to a calendar event using a service account with domain-wide delegation.

Who it is forIT and internal comms teams needing to push events to all staff calendars.
APIsAdmin SDK, Calendar API
Typical scopesadmin.directory.user.readonly, calendar

The problem

Announcing all-hands or mandatory events by email often gets ignored or lost, so adding the event directly to everyone’s calendar is the only reliable way. Manual lists go stale and break when staff join or leave.

How it works

  1. Use the Admin SDK to enumerate all active users in the domain.
  2. Construct a calendar event with all users as attendees.
  3. Insert the event via the Calendar API impersonating an organiser account.
  4. Handle batching if attendee count exceeds API limits.

What changes

Every user receives the event directly in their Google Calendar without manual invites or mailing lists.

The trap in this one. If the attendee list exceeds 200, the Calendar API silently drops additional attendees without error. The event is created, but some users never see it and there is no warning — you must batch invites or risk incomplete delivery. This is not documented in the error response; only a careful count reveals missing recipients.

Questions people ask

Can I invite groups instead of individual users?

Inviting a Google Group address only works if group settings allow external calendar invites, and group expansion in Calendar is inconsistent. Enumerating and inviting users directly is the only reliable method.

What if some users are suspended or have no calendar?

Suspended users are returned by the Admin SDK unless filtered out, but Calendar API will silently ignore invalid addresses. Always filter to active accounts before inviting.

Want this built?

This is a pattern we run in production. We will set up the delegation and build this on top of it — $500 per hour, most of it working the same day.

Talk to us Or read the setup guide

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