Twilio Send via Messaging Service

arazzo: 1.0.1
info:
  title: Twilio Send via Messaging Service
  summary: Create a messaging service, then send a message through it using the sender-pool pattern.
  description: >-
    The recommended Twilio sender-pool messaging pattern. The workflow first
    creates a new messaging service with a friendly name and optional inbound
    webhook, captures the returned messaging service SID (starts with MG), and
    then sends an SMS or MMS through that service by passing its SID as the
    MessagingServiceSid on the message create call. Sending through a messaging
    service lets Twilio pick the best sender from the pool, apply sticky sender
    and scaler behavior, and manage compliance at scale instead of pinning a
    single From number. Every step spells out its request inline so the flow can
    be read and executed without opening the underlying OpenAPI description, and
    the example inputs use Twilio magic test values so a fork runs in test mode.
  version: 1.0.0
sourceDescriptions:
- name: messagingApi
  url: ../openapi/twilio-messaging-openapi.yml
  type: openapi
workflows:
- workflowId: send-via-messaging-service
  summary: Create a messaging service and send a message through its sender pool.
  description: >-
    Creates a messaging service, then sends a message by referencing the new
    service's SID as the MessagingServiceSid, letting Twilio select a sender
    from the pool rather than a fixed From number.
  inputs:
    type: object
    required:
    - accountSid
    - friendlyName
    - to
    - body
    properties:
      accountSid:
        type: string
        description: The Twilio account SID (starts with AC) that owns the message.
        example: ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      friendlyName:
        type: string
        description: Descriptive name for the messaging service.
        example: Sender Pool Demo
      inboundRequestUrl:
        type: string
        description: Optional webhook URL for inbound messages to the service.
        example: https://example.com/twilio/inbound
      to:
        type: string
        description: Recipient phone number in E.164 format.
        example: '+15005550006'
      body:
        type: string
        description: The text content of the message (up to 1600 characters).
        example: Sent through a Twilio messaging service sender pool.
      statusCallback:
        type: string
        description: Optional URL for asynchronous status callbacks.
        example: https://example.com/twilio/status
  steps:
  - stepId: createService
    description: >-
      Create the messaging service that will own the sender pool and route the
      outbound message.
    operationId: createMessagingService
    requestBody:
      contentType: application/x-www-form-urlencoded
      payload:
        FriendlyName: $inputs.friendlyName
        InboundRequestUrl: $inputs.inboundRequestUrl
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      serviceSid: $response.body#/sid
  - stepId: sendMessage
    description: >-
      Send the message through the messaging service by passing its SID as the
      MessagingServiceSid, letting Twilio select a sender from the pool.
    operationId: createMessage
    parameters:
    - name: AccountSid
      in: path
      value: $inputs.accountSid
    requestBody:
      contentType: application/x-www-form-urlencoded
      payload:
        To: $inputs.to
        Body: $inputs.body
        MessagingServiceSid: $steps.createService.outputs.serviceSid
        StatusCallback: $inputs.statusCallback
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      messageSid: $response.body#/sid
      status: $response.body#/status
  outputs:
    serviceSid: $steps.createService.outputs.serviceSid
    messageSid: $steps.sendMessage.outputs.messageSid
    status: $steps.sendMessage.outputs.status