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OpenAPI Specification

openapi: 3.2.0
info:
  title: Paubox Email Messages API
  description: 'Public documentation for Paubox''s Transactional Email API


    ## Authentication


    **IMPORTANT**: This API uses a custom authentication format that requires the "Token token=" prefix.


    All requests must include the Authorization header in this exact format:

    ```

    Authorization: Token token=YOUR_API_KEY

    ```


    **Note for Code Generation Tools**: Auto-generated code from this specification may need to be modified to include the "Token token=" prefix, as most generators expect standard Bearer token format.

    '
  version: 1.0.0
servers:
- url: https://api.paubox.com/v1/email
  description: Paubox Email API
security:
- PauboxToken: []
tags:
- name: Messages
  description: Send individual or bulk transactional email
paths:
  /messages:
    post:
      tags:
      - Messages
      summary: Send a single email message
      operationId: sendMessage
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SingleSendRequest'
            examples:
              basic:
                summary: Minimal text+HTML example
                description: "**CURL Example:**\n```bash\ncurl --request POST \\\n  --url https://api.paubox.com/v1/email/messages \\\n  --header 'Authorization: Token token=YOUR_API_KEY' \\\n  --header 'Content-Type: application/json' \\\n  --data '{\"data\":{\"message\":{\"recipients\":[\"recipient@host.com\"],\"headers\":{\"subject\":\"Hello from the Paubox Email API\",\"from\":\"sender@verifieddomain.com\"},\"content\":{\"text/plain\":\"Hello world\",\"text/html\":\"<html><body><h1>Hello world</h1></body></html>\"}}}}'\n```\n"
                value:
                  data:
                    message:
                      recipients:
                      - recipient@host.com
                      headers:
                        subject: Hello from the Paubox Email API
                        from: sender@verifieddomain.com
                      content:
                        text/plain: Hello world
                        text/html: <html><body><h1>Hello world</h1></body></html>
              full:
                summary: Full example with bcc, reply-to, custom header, attachment, and overrides
                value:
                  data:
                    message:
                      recipients:
                      - recipient@host.com
                      - Recipient Name <recipient2@host.com>
                      bcc:
                      - recipient3@host.com
                      - Recipient Name <recipient4@host.com>
                      cc:
                      - cc.name <cc@example.com>
                      headers:
                        subject: sample email
                        from: sender@authorized_domain.com
                        reply-to: Sender Name <sender@authorized_domain.com>
                        x-custom-header: sample custom header
                        List-Unsubscribe: <mailto:unsubscribe@yourdomain.com?subject=unsubscribe>
                      content:
                        text/plain: Hello World!
                        text/html: <html><body><h1>Hello World!</h1></body></html>
                      attachments:
                      - fileName: hello_world.txt
                        contentType: text/plain
                        content: SGVsbG8gV29ybGQh
                    override_open_tracking: true
                    override_link_tracking: true
                    unsubscribe_url: https://your_url_here.com
        required: true
      responses:
        '200':
          description: Message accepted
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SingleSendResponse'
              examples:
                ok:
                  value:
                    sourceTrackingId: 3d38ab13-0af8-4028-bd45-52e882e0d584
                    customHeaders:
                      X-Custom-Header: value
                    data: Service OK
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      security:
      - PauboxToken: []
  /bulk_messages:
    post:
      tags:
      - Messages
      summary: Send multiple email messages (batch)
      description: 'Sends multiple messages in one request. Paubox recommends batches of 50 or fewer. Source tracking IDs are returned in the same order as the messages array.

        '
      operationId: sendBulkMessages
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/BulkSendRequest'
            examples:
              twoMessages:
                summary: Two-message batch
                value:
                  data:
                    messages:
                    - recipients:
                      - recipient@host.com
                      - Recipient Name <recipient@host.com>
                      bcc:
                      - recipient3@host.com
                      - Recipient Name <recipient4@host.com>
                      headers:
                        subject: sample email
                        from: sender@authorized_domain.com
                        reply-to: Sender Name <sender@authorized_domain.com>
                        x-custom-header: sample custom header
                      content:
                        text/plain: Hello World!
                        text/html: <html><body><h1>Hello World!</h1></body></html>
                      attachments:
                      - fileName: hello_world.txt
                        contentType: text/plain
                        content: SGVsbG8gV29ybGQh
                      allowNonTLS: false
                      forceSecureNotification: false
                    - recipients:
                      - recipient2@host.com
                      - Recipient Name <recipient2@host.com>
                      headers:
                        subject: sample email
                        from: sender@authorized_domain.com
                        reply-to: Sender Name <sender@authorized_domain.com>
                      content:
                        text/plain: Hello World!
                        text/html: <html><body><h1>Hello World!</h1></body></html>
                      attachments:
                      - fileName: hello_world.txt
                        contentType: text/plain
                        content: SGVsbG8gV29ybGQh
        required: true
      responses:
        '200':
          description: Batch accepted
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/BulkSendResponse'
              examples:
                ok:
                  value:
                    messages:
                    - sourceTrackingId: 3d38ab13-0af8-4028-bd45-999999999999
                      customHeaders:
                        X-Custom-Header: value
                      data: Service OK
                    - sourceTrackingId: 3d38ab13-0af8-4028-bd45-000000000000
                      customHeaders:
                        X-Custom-Header: value
                      data: Service OK
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      security:
      - PauboxToken: []
  /message_receipt:
    get:
      tags:
      - Messages
      summary: Get email disposition
      description: Retrieve delivery status, open tracking, and click tracking information for a sent message
      operationId: getMessageReceipt
      parameters:
      - name: sourceTrackingId
        in: query
        description: The tracking ID returned when the message was sent
        required: true
        schema:
          type: string
          format: uuid
          example: 6e1cf9a4-7bde-4834-8200-ed424b50c8a7
      responses:
        '200':
          description: Message disposition data
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MessageReceiptResponse'
              examples:
                delivered:
                  summary: Delivered message with open and click tracking
                  value:
                    sourceTrackingId: 6e1cf9a4-7bde-4834-8200-ed424b50c8a7
                    data:
                      message:
                        id: <f4a9b518-439c-497d-b87f-dfc9cc19194b@authorized_domain.com>
                        message_deliveries:
                        - recipient: recipient@host.com
                          status:
                            deliveryStatus: delivered
                            deliveryTime: Mon, 23 Apr 2018 13:27:34 -0700
                            openedStatus: opened
                            openedTime: Mon, 23 Apr 2018 13:27:51 -0700
                        total_opens: 1
                        distinct_opens: 1
                        total_click_count: 2
                        clicks_per_link:
                        - click_count: 1
                          target_url: amazon.com
                        - click_count: 1
                          target_url: ebay.com
                        unsubscribed: false
        '404':
          description: Message not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MessageReceiptErrorResponse'
              examples:
                notFound:
                  summary: Message not found
                  value:
                    errors:
                    - code: 404
                      title: Message was not found
                      details: Message with this tracking id was not found
                    sourceTrackingId: 6e1cf9a4-7bde-4834-8d200-ed424b50c8a7
      security:
      - PauboxToken: []
components:
  schemas:
    MessageContent:
      type: object
      properties:
        text/plain:
          type: string
          description: Plain text message body. Required if text/html is not provided.
        text/html:
          type: string
          description: 'HTML message body. May be HTML-escaped, base64-encoded, or a valid unescaped string. CSS in <style> tags will be rendered inline.

            '
      oneOf:
      - required:
        - text/plain
      - required:
        - text/html
    Attachment:
      required:
      - content
      - contentType
      - fileName
      type: object
      properties:
        fileName:
          type: string
        contentType:
          type: string
          description: Valid MIME type, e.g., application/pdf.
        content:
          type: string
          description: Base64-encoded file contents.
    SingleSendResponse:
      type: object
      properties:
        sourceTrackingId:
          type: string
          description: Identifier for tracking the message source.
        customHeaders:
          type: object
          additionalProperties:
            type: string
        data:
          type: string
          example: Service OK
    BulkSendRequest:
      required:
      - data
      type: object
      properties:
        data:
          $ref: '#/components/schemas/BulkSendRequest_data'
    ErrorResponse_errors:
      type: object
      properties:
        code:
          type: integer
        title:
          type: string
        details:
          type: string
    MessageReceiptResponse_data:
      required:
      - message
      type: object
      properties:
        message:
          $ref: '#/components/schemas/MessageReceiptResponse_data_message'
    MessageDelivery:
      required:
      - recipient
      - status
      type: object
      properties:
        recipient:
          type: string
          description: The recipient email address
          example: recipient@host.com
        status:
          $ref: '#/components/schemas/DeliveryStatus'
    Message:
      required:
      - content
      - headers
      - recipients
      type: object
      properties:
        recipients:
          minItems: 1
          type: array
          items:
            type: string
            description: Email address, optionally with display name (e.g., "J. Smith <jsmith@host.com>").
        bcc:
          type: array
          items:
            type: string
        cc:
          type: array
          items:
            type: string
        headers:
          $ref: '#/components/schemas/MessageHeaders'
        allowNonTLS:
          type: boolean
          description: 'Allow delivery over non-TLS rather than converting to a Secure Portal message. Not HIPAA compliant if the message contains PHI.

            '
          default: false
        forceSecureNotification:
          type: boolean
          description: 'Force delivery as a Paubox Secure Message; recipient gets a pickup notification with a link.

            '
          default: false
        content:
          $ref: '#/components/schemas/MessageContent'
        attachments:
          type: array
          items:
            $ref: '#/components/schemas/Attachment'
    BulkSendResponse_messages:
      type: object
      properties:
        sourceTrackingId:
          type: string
        customHeaders:
          type: object
          additionalProperties:
            type: string
        data:
          type: string
          example: Service OK
    MessageHeaders:
      required:
      - from
      - subject
      type: object
      properties:
        subject:
          type: string
        from:
          type: string
          description: Must match the verified domain of your API key.
        reply-to:
          type: string
          description: Reply-to address; must match a verified domain if different from from.
        List-Unsubscribe:
          type: string
          description: 'Insert a List-Unsubscribe header (mailto and/or http). See RFC guidance for syntax.

            '
        List-Unsubscribe-Post:
          type: string
          description: Used in conjunction with List-Unsubscribe header.
        x-custom-header:
          type: string
          description: Example custom header; any custom header may be added with an X- prefix.
        additionalProperties:
          type: string
          description: Any additional X- prefixed custom header values.
    SingleSendRequest:
      required:
      - data
      type: object
      properties:
        data:
          $ref: '#/components/schemas/SingleSendRequest_data'
    ErrorResponse:
      type: object
      properties:
        errors:
          type: array
          items:
            $ref: '#/components/schemas/ErrorResponse_errors'
    ClickData:
      required:
      - click_count
      - target_url
      type: object
      properties:
        click_count:
          type: integer
          description: Number of clicks on this specific link
          example: 1
        target_url:
          type: string
          description: The URL that was clicked
          example: amazon.com
    SingleSendRequest_data:
      required:
      - message
      type: object
      properties:
        message:
          $ref: '#/components/schemas/Message'
        override_open_tracking:
          type: boolean
          description: Set to true to enable open tracking for this message.
        override_link_tracking:
          type: boolean
          description: Set to true to enable click tracking for this message (up to 1000 links).
        unsubscribe_url:
          type: string
          description: URL to redirect unsubscribe requests for unsubscribe tracking.
          format: uri
    MessageReceiptResponse:
      required:
      - data
      - sourceTrackingId
      type: object
      properties:
        sourceTrackingId:
          type: string
          description: The tracking ID for the message
          example: 6e1cf9a4-7bde-4834-8200-ed424b50c8a7
        data:
          $ref: '#/components/schemas/MessageReceiptResponse_data'
    BulkSendRequest_data:
      required:
      - messages
      type: object
      properties:
        messages:
          type: array
          description: Recommended 50 or fewer per request.
          items:
            $ref: '#/components/schemas/Message'
    MessageReceiptResponse_data_message:
      required:
      - id
      - message_deliveries
      type: object
      properties:
        id:
          type: string
          description: The message ID
          example: <f4a9b518-439c-497d-b87f-dfc9cc19194b@authorized_domain.com>
        message_deliveries:
          type: array
          items:
            $ref: '#/components/schemas/MessageDelivery'
        total_opens:
          type: integer
          description: Total number of opens (single recipient only)
          example: 1
        distinct_opens:
          type: integer
          description: Number of distinct opens (single recipient only)
          example: 1
        total_click_count:
          type: integer
          description: Total number of clicks (single recipient only)
          example: 2
        clicks_per_link:
          type: array
          description: Click tracking data per link (single recipient only)
          items:
            $ref: '#/components/schemas/ClickData'
        unsubscribed:
          type: boolean
          description: Whether the recipient has unsubscribed (single recipient only)
          example: false
    MessageReceiptErrorResponse:
      required:
      - errors
      - sourceTrackingId
      type: object
      properties:
        errors:
          type: array
          items:
            $ref: '#/components/schemas/ErrorResponse_errors'
        sourceTrackingId:
          type: string
          description: The tracking ID for the message
          example: 6e1cf9a4-7bde-4834-8d200-ed424b50c8a7
    DeliveryStatus:
      required:
      - deliveryStatus
      type: object
      properties:
        deliveryStatus:
          type: string
          description: The delivery status of the message
          example: delivered
          enum:
          - processing
          - TLS not offered, sending via Secure Portal
          - soft bounced
          - soft bounced - mailbox full
          - hard bounced
          - Internal error. Please check back later.
          - delivered
          - delivered via secure portal
        deliveryTime:
          type: string
          description: The time when the message was delivered (if applicable)
          example: Mon, 23 Apr 2018 13:27:34 -0700
        openedStatus:
          type: string
          description: Whether the message was opened (single recipient only)
          example: opened
          enum:
          - opened
          - not opened
        openedTime:
          type: string
          description: The time when the message was first opened (single recipient only)
          example: Mon, 23 Apr 2018 13:27:51 -0700
    BulkSendResponse:
      type: object
      properties:
        messages:
          type: array
          items:
            $ref: '#/components/schemas/BulkSendResponse_messages'
  securitySchemes:
    PauboxToken:
      type: http
      scheme: bearer
      description: 'Paubox API uses Bearer token authentication in the Authorization header.


        Format: `Authorization: Bearer YOUR_API_KEY_HERE`


        Example: `Authorization: Bearer 9e5b092b632445b8f570c62ae54f30fda1044305`


        The legacy format `Authorization: Token token=YOUR_API_KEY_HERE` is also supported.

        '