openapi: 3.0.1
info:
  title: Twilio - Accounts A2p Mail Send API
  description: This is the public Twilio REST API.
  termsOfService: https://www.twilio.com/legal/tos
  contact:
    name: Twilio Support
    url: https://support.twilio.com
    email: support@twilio.com
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0.html
  version: 1.52.0
servers:
- url: https://accounts.twilio.com
tags:
- name: Mail Send
  description: Send email messages
paths:
  /mail/send:
    post:
      operationId: sendEmail
      summary: Twilio Send an Email
      description: Send an email message to one or more recipients. Supports personalizations, dynamic templates, attachments, categories, and scheduling.
      tags:
      - Mail Send
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendEmailRequest'
      responses:
        '202':
          description: Email accepted for delivery
        '400':
          description: Invalid request
        '401':
          description: Unauthorized
        '413':
          description: Payload too large
        '429':
          description: Rate limit exceeded
components:
  schemas:
    SendEmailRequest:
      type: object
      required:
      - personalizations
      - from
      properties:
        personalizations:
          type: array
          items:
            $ref: '#/components/schemas/Personalization'
          minItems: 1
          maxItems: 1000
          description: Recipients and per-recipient settings
        from:
          $ref: '#/components/schemas/EmailAddress'
        reply_to:
          $ref: '#/components/schemas/EmailAddress'
        reply_to_list:
          type: array
          items:
            $ref: '#/components/schemas/EmailAddress'
          maxItems: 1000
        subject:
          type: string
          description: Global subject line
        content:
          type: array
          items:
            type: object
            required:
            - type
            - value
            properties:
              type:
                type: string
                description: MIME type (text/plain or text/html)
              value:
                type: string
                description: Content body
        attachments:
          type: array
          items:
            $ref: '#/components/schemas/Attachment'
        template_id:
          type: string
          description: ID of a dynamic template to use
        headers:
          type: object
          additionalProperties:
            type: string
        categories:
          type: array
          items:
            type: string
          maxItems: 10
          description: Categories for tracking (max 10)
        send_at:
          type: integer
          description: Unix timestamp for scheduled send (up to 72 hours)
        batch_id:
          type: string
          description: Batch ID for grouping scheduled sends
        asm:
          type: object
          properties:
            group_id:
              type: integer
              description: Unsubscribe group ID
            groups_to_display:
              type: array
              items:
                type: integer
              maxItems: 25
        ip_pool_name:
          type: string
          description: Name of the IP pool for sending
        tracking_settings:
          type: object
          properties:
            click_tracking:
              type: object
              properties:
                enable:
                  type: boolean
                enable_text:
                  type: boolean
            open_tracking:
              type: object
              properties:
                enable:
                  type: boolean
                substitution_tag:
                  type: string
            subscription_tracking:
              type: object
              properties:
                enable:
                  type: boolean
    EmailAddress:
      type: object
      required:
      - email
      properties:
        email:
          type: string
          format: email
        name:
          type: string
    Attachment:
      type: object
      required:
      - content
      - filename
      properties:
        content:
          type: string
          description: Base64 encoded attachment content
        filename:
          type: string
        type:
          type: string
          description: MIME type of the attachment
        disposition:
          type: string
          enum:
          - inline
          - attachment
          default: attachment
        content_id:
          type: string
          description: Content ID for inline attachments
    Personalization:
      type: object
      required:
      - to
      properties:
        to:
          type: array
          items:
            $ref: '#/components/schemas/EmailAddress'
          minItems: 1
        cc:
          type: array
          items:
            $ref: '#/components/schemas/EmailAddress'
        bcc:
          type: array
          items:
            $ref: '#/components/schemas/EmailAddress'
        subject:
          type: string
        headers:
          type: object
          additionalProperties:
            type: string
        substitutions:
          type: object
          additionalProperties:
            type: string
        dynamic_template_data:
          type: object
          description: Dynamic template handlebars data
        custom_args:
          type: object
          additionalProperties:
            type: string
        send_at:
          type: integer
  securitySchemes:
    accountSid_authToken:
      type: http
      scheme: basic
x-maturity:
- name: GA
  description: This product is Generally Available.
- name: Beta
  description: PLEASE NOTE that this is a Beta product that is subject to change. Use it with caution.