openapi: 3.0.3
info:
  title: AT&T In-App Messaging Authentication Device Management API
  description: A messaging API enabling applications to send, receive, update, and delete MMS and SMS messages on behalf of AT&T users with explicit OAuth consent. Supports messages to phone numbers, short codes, and email addresses across AT&T and other carriers with full inbox management and delta synchronization.
  version: '2.0'
  contact:
    url: https://developer.att.com/support
  termsOfService: https://www.att.com/gen/general?pid=11561
  x-generated-from: documentation
  x-last-validated: '2026-04-19'
servers:
- url: https://api.att.com
  description: AT&T API Gateway
tags:
- name: Device Management
paths:
  /resource:
    get:
      operationId: listResources
      summary: AT&T List Devices and SIMs
      description: Retrieve device details and SIM information for subscribers. Corresponds to TMF 639 Resource Inventory API.
      tags:
      - Device Management
      parameters:
      - name: relatedParty.id
        in: query
        required: false
        description: Filter resources by subscriber ID
        schema:
          type: string
          example: sub-a1b2c3d4
      responses:
        '200':
          description: Resources successfully retrieved
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/Resource'
              examples:
                ListResources200Example:
                  summary: Default listResources 200 response
                  x-microcks-default: true
                  value:
                  - id: resource-500123
                    name: Samsung Galaxy S25
                    resourceType: device
                    status: active
                    serialNumber: IMEI-123456789012345
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      x-microcks-operation:
        delay: 0
        dispatcher: FALLBACK
  /resource/{id}:
    get:
      operationId: getResource
      summary: AT&T Get Device or SIM Status
      description: Retrieve the current status and details of a specific device or SIM card. Corresponds to TMF 639 Resource Inventory API.
      tags:
      - Device Management
      parameters:
      - name: id
        in: path
        required: true
        description: Resource (device or SIM) ID
        schema:
          type: string
          example: resource-500123
      responses:
        '200':
          description: Resource details retrieved
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Resource'
              examples:
                GetResource200Example:
                  summary: Default getResource 200 response
                  x-microcks-default: true
                  value:
                    id: resource-500123
                    name: Samsung Galaxy S25
                    resourceType: device
                    status: active
                    serialNumber: IMEI-123456789012345
        '404':
          description: Resource not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      x-microcks-operation:
        delay: 0
        dispatcher: FALLBACK
    patch:
      operationId: updateResource
      summary: AT&T Update Resource (Reset Voicemail Password)
      description: Update a resource attribute, such as resetting the voicemail password for a subscriber's device. Corresponds to TMF 702 Resource Activation and Configuration API.
      tags:
      - Device Management
      parameters:
      - name: id
        in: path
        required: true
        description: Resource ID
        schema:
          type: string
          example: resource-500123
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ResourceUpdate'
            examples:
              UpdateResourceRequestExample:
                summary: Default updateResource request
                x-microcks-default: true
                value:
                  resourceCharacteristic:
                  - name: voicemailPassword
                    value: '1234'
      responses:
        '200':
          description: Resource successfully updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Resource'
              examples:
                UpdateResource200Example:
                  summary: Default updateResource 200 response
                  x-microcks-default: true
                  value:
                    id: resource-500123
                    status: active
        '404':
          description: Resource not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      x-microcks-operation:
        delay: 0
        dispatcher: FALLBACK
components:
  schemas:
    ErrorResponse:
      type: object
      properties:
        code:
          type: string
          description: Error code
          example: '400'
        reason:
          type: string
          description: Short reason for the error
          example: Bad Request
        message:
          type: string
          description: Detailed error message
          example: Invalid input parameter value
        status:
          type: string
          description: HTTP status code
          example: '400'
    Resource:
      type: object
      properties:
        id:
          type: string
          description: Unique resource identifier
          example: resource-500123
        name:
          type: string
          description: Device or SIM name
          example: Samsung Galaxy S25
        resourceType:
          type: string
          description: Type of resource
          enum:
          - device
          - sim
          example: device
        status:
          type: string
          description: Resource operational status
          enum:
          - active
          - inactive
          - suspended
          example: active
        serialNumber:
          type: string
          description: Device IMEI or SIM ICCID
          example: IMEI-123456789012345
    ResourceUpdate:
      type: object
      properties:
        resourceCharacteristic:
          type: array
          items:
            type: object
            properties:
              name:
                type: string
                description: Characteristic name to update
                example: voicemailPassword
              value:
                type: string
                description: New value for the characteristic
                example: '1234'
  securitySchemes:
    oauth2:
      type: oauth2
      description: AT&T OAuth 2.0 with user consent via authorization code flow
      flows:
        authorizationCode:
          authorizationUrl: https://api.att.com/oauth/v4/authorize
          tokenUrl: https://api.att.com/oauth/v4/token
          scopes:
            IMMN: Send Message - send MMS and SMS messages on behalf of user
            MIM: Message Inbox Management - read, update, and delete messages