> ## Documentation Index
> Fetch the complete documentation index at: https://docs.photon.codes/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Add a dedicated iMessage line

> Allocates a new dedicated iMessage phone number for the project and updates the Stripe subscription quantity with pro-rated billing. Business plan only. iMessage only for now; WhatsApp Business onboarding flows through the Meta registration endpoints. Requires Authorization: Basic base64(projectId:projectSecret).



## OpenAPI

````yaml https://spectrum.photon.codes/openapi/json post /projects/{projectId}/lines/
openapi: 3.1.0
info:
  title: Spectrum Cloud External API
  description: Client-facing API for Spectrum Cloud.
  version: 1.0.0
servers:
  - url: https://spectrum.photon.codes
security: []
tags:
  - name: billing
    description: Billing and subscription operations
  - name: imessage
    description: iMessage platform operations
  - name: lines
    description: Phone line enumeration across platforms
  - name: platforms
    description: Platform management operations
  - name: users
    description: User operations
  - name: voice
    description: Voice platform operations
  - name: webhooks
    description: Webhook registration for receiving Spectrum events
  - name: whatsapp-business
    description: WhatsApp Business platform operations
  - name: slack
    description: Slack platform operations
paths:
  /projects/{projectId}/lines/:
    post:
      tags:
        - lines
      summary: Add a dedicated iMessage line
      description: >-
        Allocates a new dedicated iMessage phone number for the project and
        updates the Stripe subscription quantity with pro-rated billing.
        Business plan only. iMessage only for now; WhatsApp Business onboarding
        flows through the Meta registration endpoints. Requires Authorization:
        Basic base64(projectId:projectSecret).
      operationId: postProjectsByProjectIdLines
      parameters:
        - name: projectId
          in: path
          required: true
          schema:
            type: string
            format: uuid
            pattern: >-
              ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                platform:
                  type: string
                  const: imessage
              required:
                - platform
              additionalProperties: false
          application/x-www-form-urlencoded:
            schema:
              type: object
              properties:
                platform:
                  type: string
                  const: imessage
              required:
                - platform
              additionalProperties: false
          multipart/form-data:
            schema:
              type: object
              properties:
                platform:
                  type: string
                  const: imessage
              required:
                - platform
              additionalProperties: false
      responses:
        '200':
          description: Response for status 200
          content:
            application/json:
              schema:
                type: object
                properties:
                  succeed:
                    type: boolean
                    const: true
                  data:
                    type: object
                    properties:
                      line:
                        type: object
                        properties:
                          platform:
                            type: string
                            const: imessage
                          id:
                            type: string
                            format: uuid
                            pattern: >-
                              ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$
                          phoneNumber:
                            type: string
                          status:
                            type: string
                            enum:
                              - available
                              - unavailable
                              - unknown
                          createdAt:
                            type: string
                        required:
                          - platform
                          - id
                          - phoneNumber
                          - status
                          - createdAt
                        additionalProperties: false
                      billing:
                        type: object
                        properties:
                          quantity:
                            anyOf:
                              - type: number
                              - type: 'null'
                          prorationAmount:
                            anyOf:
                              - type: number
                              - type: 'null'
                          syncStatus:
                            type: string
                            enum:
                              - in_sync
                              - syncing
                              - failed
                        required:
                          - quantity
                          - prorationAmount
                          - syncStatus
                        additionalProperties: false
                    required:
                      - line
                      - billing
                    additionalProperties: false
                required:
                  - succeed
                  - data
                additionalProperties: false

````