openapi: 3.1.0
info:
  title: Cellulant Tingg Engage API
  description: |
    Tingg Engage — single global entry point for transactional alerts.
    Send SMS (OTP, transactional, standard) to customers with templated
    parameters and delivery status callbacks.
  version: "2.0.0"
  contact:
    name: Cellulant Developer Support
    url: https://developer.tingg.africa
    email: developer@cellulant.io
servers:
  - url: https://api.tingg.africa
    description: Production
  - url: https://api-test.tingg.africa
    description: Sandbox
security:
  - BearerAuth: []
tags:
  - name: Engagement
    description: Outbound SMS notifications and OTPs.
paths:
  /api/v2/engagement:
    post:
      summary: Send Engagement Message
      description: Queue an SMS notification (OTP, transactional, or standard). Delivery status is reported via callback to the supplied callbackUrl.
      operationId: sendEngagement
      tags:
        - Engagement
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/EngagementRequest'
            examples:
              SmsEngagementExample:
                $ref: '#/components/examples/SmsEngagementExample'
      responses:
        '200':
          description: Message queued
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EngagementResponse'
              examples:
                EngagementResponseExample:
                  $ref: '#/components/examples/EngagementResponseExample'
        '4XX':
          $ref: '#/components/responses/ErrorResponse'
components:
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
  responses:
    ErrorResponse:
      description: Error response
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    EngagementRequest:
      type: object
      required: [notificationType, channels, referenceID, smsDto]
      properties:
        notificationType:
          type: string
          enum: [OTP, TRX, STANDARD, SMS_TEST]
        channels:
          type: array
          items:
            type: string
            enum: [SMS]
        referenceID:
          type: string
        callbackUrl:
          type: string
          format: uri
        smsDto:
          $ref: '#/components/schemas/SmsDto'
    SmsDto:
      type: object
      required: [msisdn, message]
      properties:
        msisdn:
          type: array
          items:
            type: string
          description: One or more recipient phone numbers in E.164 format.
        message:
          type: string
          description: Message body; supports `${placeholder}` substitution.
        params:
          type: object
          additionalProperties:
            type: string
        senderID:
          type: string
    EngagementResponse:
      type: object
      properties:
        transactionID:
          type: string
          format: uuid
        statusCode:
          type: integer
          example: 200
        message:
          type: string
    Error:
      type: object
      properties:
        statusCode:
          type: integer
        message:
          type: string
  examples:
    SmsEngagementExample:
      summary: Send a templated OTP
      value:
        notificationType: OTP
        channels: [SMS]
        referenceID: ref-cas-123
        callbackUrl: https://merchant.example.co.ke/sms/callback
        smsDto:
          msisdn: ['254712345678']
          message: 'Your Tingg OTP is ${code}. Valid for 5 minutes.'
          params:
            code: '648291'
          senderID: TINGG
    EngagementResponseExample:
      summary: Message queued
      value:
        transactionID: 8f6b2c80-43f7-4f78-b1d2-7a3a5d6c1e0a
        statusCode: 200
        message: Message queued successfully.