domainwidedelegation.comStart free

Use cases → Scheduling

Detect event conflicts across multiple calendars automatically

Identify overlapping events on several user or resource calendars before booking or scheduling, using a delegated service account.

Who it is forAny team or automation responsible for booking meetings or resources across several calendars.
APIsCalendar API
Typical scopescalendar.readonly

The problem

People and resources are double-booked when calendars are not checked together, especially in shared spaces or pooled resource scenarios. Manual checks are slow and unreliable, particularly across organisational boundaries or secondary calendars.

How it works

  1. Impersonate each relevant calendar owner using the service account.
  2. Query each calendar’s events for the target time range.
  3. Compare the returned events for overlaps on start/end times.
  4. Report all collisions, including the conflicting event details and calendar identifiers.

What changes

Double bookings are caught before they happen, and scheduling tools can show a precise reason for rejection.

The trap in this one. The Calendar API’s events.list endpoint may return stale or incomplete results for secondary calendars if recent permissions or sharing changes haven’t fully propagated. In practice, a new shared calendar or updated ACL may take minutes to become queryable, causing false negatives where conflicts are missed. Always allow for propagation lag before trusting the result, especially after calendar creation or sharing changes.

Questions people ask

Can I fetch all calendars in one call?

No. You must query each calendar individually for its events, and you need to know the calendar IDs in advance.

Does this work for external calendars?

Only if they are added as secondary calendars and the service account has been granted access.

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

Related use cases

Build a real picture of team availability

Read calendars across the domain to answer who is free, who is overloaded and where the week actually went.

Turn a finished meeting into follow-up automatically

Detect that a meeting happened, pull the notes, and draft the follow-up before anyone opens their laptop.

Turn a booking into a record everywhere it matters

When a meeting is booked, create the record, the folder and the confirmation in one pass.