> ## Documentation Index
> Fetch the complete documentation index at: https://cal.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Message an Event's guests

> Emails one segment of the Event's guests, optionally narrowed to one location or to guests who did or did not check in. Guests who have only a phone number are texted instead when texting is available; `textRecipientCount` says how many. The message is queued and sent in the background, or at `scheduledAt` when you give one; list the Event's messages to follow its status. The authenticated user must be the Event's owner, one of its hosts, or a member of the owning team. Co-hosts cannot message guests. PBAC permission for team events: `calEvent.update`. If accessed using an OAuth access token, the `EVENT_WRITE` scope is required.



## OpenAPI

````yaml /api-reference/v2/openapi.json post /v2/events/{uuid}/messages
openapi: 3.0.0
info:
  title: Cal.com API v2
  description: ''
  version: 1.0.0
  contact: {}
servers: []
security: []
tags: []
paths:
  /v2/events/{uuid}/messages:
    post:
      tags:
        - Events
      summary: Message an Event's guests
      description: >-
        Emails one segment of the Event's guests, optionally narrowed to one
        location or to guests who did or did not check in. Guests who have only
        a phone number are texted instead when texting is available;
        `textRecipientCount` says how many. The message is queued and sent in
        the background, or at `scheduledAt` when you give one; list the Event's
        messages to follow its status. The authenticated user must be the
        Event's owner, one of its hosts, or a member of the owning team.
        Co-hosts cannot message guests. PBAC permission for team events:
        `calEvent.update`. If accessed using an OAuth access token, the
        `EVENT_WRITE` scope is required.
      operationId: EventMessagesController_sendMessage
      parameters:
        - name: uuid
          required: true
          in: path
          description: >-
            Event UUID. Accepts the canonical UUID (e.g.
            `018ff5cd-6dc4-7d57-bcbc-374702ca8b38`) or its short-uuid (Flickr
            Base58) form (e.g. `1cbZYoAFoJdwqN4tixezd5`).
          schema:
            type: string
            format: uuid
        - name: Authorization
          in: header
          description: >-
            value must be `Bearer <token>` where `<token>` is api key prefixed
            with cal_, managed user access token, or OAuth access token
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendMessageInput'
      responses:
        '200':
          description: ''
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SendMessageOutputResponseDto'
        '400':
          description: >-
            Invalid Event UUID or body, the segment has no guests to email, the
            Event no longer accepts messages, or `scheduledAt` is too soon or
            after messages close
        '401':
          description: Unauthenticated
        '403':
          description: Insufficient permissions
        '404':
          description: Event not found
        '429':
          description: Rate limit exceeded
components:
  schemas:
    SendMessageInput:
      type: object
      properties:
        segment:
          enum:
            - GOING
            - MAYBE
            - PENDING
          type: string
          description: >-
            Which guests receive the message: `GOING` (confirmed, RSVP yes),
            `MAYBE` (confirmed, RSVP maybe) or `PENDING` (waiting for approval).
        subject:
          type: string
          description: Email subject in plain text, up to 200 characters. HTML is refused.
        body:
          type: string
          description: >-
            Message in plain text, up to 5000 characters. Links are allowed as
            plain URLs; HTML is refused.
        scheduledAt:
          type: string
          description: >-
            When to send the message, as an ISO 8601 date-time such as
            `2030-01-01T09:00:00Z`. It must be at least 5 minutes from now and
            earlier than 7 days after the Event ends. Omit it to send the
            message now. Cancel a scheduled message before this time with the
            cancel endpoint.
          example: '2030-01-01T09:00:00Z'
        locationId:
          type: string
          maxLength: 128
          description: Only message guests who registered for this location of the Event.
        checkedIn:
          type: boolean
          description: >-
            Only message guests who checked in (`true`) or who did not
            (`false`). Omit to message both.
      required:
        - segment
        - subject
        - body
    SendMessageOutputResponseDto:
      type: object
      properties:
        status:
          enum:
            - success
            - error
          type: string
          example: success
        data:
          $ref: '#/components/schemas/SendMessageOutputDto'
      required:
        - status
        - data
    SendMessageOutputDto:
      type: object
      properties:
        id:
          type: string
          description: Unique identifier of the message.
        status:
          enum:
            - QUEUED
            - FAILED_TO_QUEUE
          type: string
          description: >-
            `QUEUED` when the message is on its way, or waiting for its
            `scheduledAt`; `FAILED_TO_QUEUE` when it could not be queued and
            nothing was sent.
        scheduledAt:
          format: date-time
          type: string
          description: When the message will be sent. Present only for a scheduled message.
        recipientCount:
          type: number
          description: How many guests will be emailed.
        textRecipientCount:
          type: number
          description: >-
            How many guests will be texted instead, because they have only a
            phone number.
        skippedPhoneCount:
          type: number
          description: >-
            Guests in the segment who have only a phone number and will not be
            texted.
      required:
        - id
        - status
        - recipientCount
        - textRecipientCount
        - skippedPhoneCount

````

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