---
title: "Validate time slot"
method: POST
path: "/v3/scheduling/configurations/{configuration_id}/group-events/validate-timeslot"
tags: ["Group Events"]
---

# Validate time slot

`POST /v3/scheduling/configurations/{configuration_id}/group-events/validate-timeslot`

## Request

- Base URL: `https://api.us.nylas.com`
- URL: `https://api.us.nylas.com/v3/scheduling/configurations/{configuration_id}/group-events/validate-timeslot`
- Auth: HTTP bearer

Validates whether the selected group event or time slot has changed, and is invalid. This can happen
because...

- The group event was deleted.
- The group event was updated (for example, the start time was changed).
- The `capacity` for the event was changed.

## Request body

- object
  - `calendar_id` string, required: ID of the calendar to access.
  - `capacity` number: The maximum number of attendees for the event. If not specified, Nylas uses the default capacity for your Configuration.
  - `end_time` integer, required: The end time of the time slot, in seconds using the Unix timestamp format. Nylas compares this to the event's current end time to detect whether it was rescheduled.
  - `emails` string[]: A list of email addresses associated with the event's participants.
  - `event_id` string, required: ID of the event to validate.
  - `master_id` string: The master event ID. Required when working with recurring events.
  - `start_time` integer, required: The start time of the time slot, in seconds using the Unix timestamp format. Nylas compares this to the event's current start time to detect whether it was rescheduled.

## Response `200`

Time slot validated

- object
  - `request_id` string: ID of the request.

## Other responses

- `400`: Bad Request
- `401`: Unauthorized
- `404`: Not Found
- `429`: Rate limited. The provider or Nylas throttled the request. If a provider throttles a request and says how long to wait, the `Retry-After` header gives that number of seconds. When the header is missing, retry with exponential backoff. See [429 rate limit errors by provider](/docs/api/errors/400-response/#429-rate-limit-errors-by-provider).

## Changes

- **2026-09-29** `a669a04b02ba`: 2 breaking, 4 info
  - added the new required request property `end_time`
  - added the new required request property `start_time`
  - added the non-success response with the status `400`
  - added the non-success response with the status `401`
  - …2 more

[Operation history](https://skmtc.dev/nylas/apis/nylas-api/changes/v3/scheduling/configurations/:configuration_id/group-events/validate-timeslot/post.md)

---

[API](https://skmtc.dev/nylas/apis/nylas-api.md) - [All operations](https://skmtc.dev/nylas/apis/nylas-api/llms.txt) - [OpenAPI document](https://skmtc.dev/nylas/apis/nylas-api/revisions/7782a3e3ab70?raw)