Sinch Transcoding API

openapi: 3.2.0
info:
  title: Sinch Conversation Transcoding API
  description: The Sinch Conversation API is an omnichannel messaging platform that enables developers to send and receive messages across multiple channels including SMS, RCS, WhatsApp, Facebook Messenger, Instagram, Viber, Telegram, KakaoTalk, and LINE through a single unified API. It provides contact management, conversation tracking, message templating, and webhook callbacks for real-time event handling. The API normalizes message formats across channels, allowing developers to build multichannel messaging experiences without channel-specific integrations.
  version: '1.0'
  contact:
    name: Sinch Support
    url: https://www.sinch.com/contact-us/
  termsOfService: https://www.sinch.com/terms-of-service/
servers:
- url: https://us.conversation.api.sinch.com
  description: US Production Server
- url: https://eu.conversation.api.sinch.com
  description: EU Production Server
- url: https://br.conversation.api.sinch.com
  description: Brazil Production Server
security:
- oAuth2: []
- basicAuth: []
tags:
- name: Transcoding
  description: Transcode generic message formats to channel-specific formats for preview purposes.
paths:
  /v1/projects/{project_id}/messages:transcode:
    post:
      operationId: transcodeMessage
      summary: Transcode a Message
      description: Transcodes a generic message format to a channel-specific format for preview purposes without sending the message.
      tags:
      - Transcoding
      parameters:
      - $ref: '#/components/parameters/ProjectId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/TranscodeRequest'
      responses:
        '200':
          description: Transcoded message
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TranscodeResponse'
        '400':
          description: Invalid request
        '401':
          description: Unauthorized
components:
  parameters:
    ProjectId:
      name: project_id
      in: path
      required: true
      description: The unique project identifier
      schema:
        type: string
  schemas:
    TranscodeRequest:
      type: object
      required:
      - app_id
      - app_message
      - channels
      properties:
        app_id:
          type: string
          description: The app ID
        app_message:
          $ref: '#/components/schemas/AppMessage'
        channels:
          type: array
          description: Target channels for transcoding
          items:
            type: string
    TranscodeResponse:
      type: object
      properties:
        transcoded_message:
          type: object
          description: Map of channel to transcoded message
          additionalProperties:
            type: string
    AppMessage:
      type: object
      properties:
        text_message:
          type: object
          description: A text message
          properties:
            text:
              type: string
              description: The message text
        media_message:
          type: object
          description: A media message
          properties:
            url:
              type: string
              format: uri
              description: The media URL
            thumbnail_url:
              type: string
              format: uri
              description: The thumbnail URL
        template_message:
          type: object
          description: A template message
          properties:
            omni_template:
              type: object
              description: The template reference
              properties:
                template_id:
                  type: string
                  description: The template identifier
                version:
                  type: string
                  description: The template version
                language_code:
                  type: string
                  description: The language code
                parameters:
                  type: object
                  description: Template parameter values
        card_message:
          type: object
          description: A card message with title, description, and media
          properties:
            title:
              type: string
              description: The card title
            description:
              type: string
              description: The card description
            media_message:
              type: object
              description: The card media
              properties:
                url:
                  type: string
                  format: uri
                  description: The media URL
            choices:
              type: array
              description: Action choices on the card
              items:
                $ref: '#/components/schemas/Choice'
        list_message:
          type: object
          description: A list message with sections
          properties:
            title:
              type: string
              description: The list title
            description:
              type: string
              description: The list description
            sections:
              type: array
              description: List sections
              items:
                type: object
                properties:
                  title:
                    type: string
                    description: Section title
                  items:
                    type: array
                    description: Section items
                    items:
                      $ref: '#/components/schemas/Choice'
    Choice:
      type: object
      properties:
        text_message:
          type: object
          description: Text choice
          properties:
            text:
              type: string
              description: The choice text
        postback_data:
          type: string
          description: Data sent back when the choice is selected
  securitySchemes:
    oAuth2:
      type: oauth2
      description: OAuth 2.0 client credentials flow using project key ID and secret.
      flows:
        clientCredentials:
          tokenUrl: https://auth.sinch.com/oauth2/token
          scopes: {}
    basicAuth:
      type: http
      scheme: basic
      description: Key ID as username and key secret as password.
externalDocs:
  description: Sinch Conversation API Documentation
  url: https://developers.sinch.com/docs/conversation