Handling of pending and cancelled calendar events for attendees (Outlook behavior)

Question and Answers
1

Hello,

I have 2 questions regarding how Nylas handles attendee states and cancelled calendar events, especially compared to Outlook behavior.

Scenario 1 – Event created, attendee has not responded

  • Organizer creates a calendar event and adds the attendee

  • Attendee receives the invitation email

  • In Outlook, the attendee sees:

    • a calendar entry that is not accepted or declined

    • the event is not colored (pending / no response)

Question:
Is it possible via Nylas to retrieve an attendee state that represents
“invited but not yet accepted or declined”?

Scenario 2 – Event cancelled by organizer
  • Organizer cancels the event
  • Attendee receives a cancellation email with an .ics file in our software.
  • In Outlook:
    • the cancellation email still shows the original date and time
    • the calendar entry appears as “Cancelled: ”
    • the event is not colored but remains visible for reference

Current behavior in our software:

  • The cancellation email is received correctly
  • The .ics file cannot be opened because the event no longer exists
  • As a result, we lose access to:
    • event date
    • event time
    • cancelled-event context

Questions:

  • Can Nylas still provide the original date and time of a cancelled event for attendees?
  • Is there a way to identify a cancelled event state (similar to Outlook’s “Cancelled: ”)?

Thanks and Best Regards,

Aida

2

Hello Aida,

Thanks for your questions, happy to help.

Scenario 1:
Yes, Nylas supports this. You can check the participant_status field. If it’s set to noreply, it means the attendee has been invited but hasn’t responded yet. Other possible values are yes, no, and maybe.

Scenario 2:
Yes to both of your questions.

  • Original date and time: Nylas keeps cancelled events in a soft-deleted state, so the start, end, and other details are still available.

  • Cancelled state: The status field will be set to cancelled, similar to how Outlook marks events as “Cancelled:”.

Best practice:

  • Use webhooks to listen for event.updated or event.deleted when cancellations happen.
    Webhooks

  • Query the API with show_cancelled=true to get the full event details, including the original date and time.
    show_cancelled=true docs

  • For recurring events, look for the original_start_time field on the cancelled instance.

Let me know if you need any help.

Many thanks,
Samuel R.
Support Engineer, Nylas

1 Like
3

Hello Samuel,

thank you for your helpful respond !