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

> Connect app voice call through the Voice SDK integration. Use with the authentication and customer identity flow described in the app voice guide.

# Start a connected app voice call

See [Voice SDK integration](/phone/voice-sdk) for authentication, platform packages, routing, and preview availability.

The SDK calls this after joining and publishing microphone audio. Use `Authorization: Bearer <controlToken>` from call creation. Only this OpenCX call token is accepted for call control; permanent API keys are not accepted. Use the SDK to manage the audio connection before activation.

Returns HTTP 200 with `{ "success": true }`. Repeated activation of an active call is safe. Expired or ended calls, missing microphone publication, and unavailable support return 409. A failed activation ends its reserved call; begin a new call attempt with a new request ID.


## OpenAPI

````yaml post /phone/web-calls/{callId}/connect
openapi: 3.1.0
info:
  title: OpenCX API
  description: >

    OpenCX is an AI-powered, all-in-one platform for customer support and
    outbound communications.


    Use this API to manage your OpenCX organization's AI agents, actions,
    conversations, contacts, and more.


    To get started, generate a new API key from the dashboard.


    ## Authentication

    All API endpoints require authentication using a Bearer token. You can
    generate an API key from your OpenCX dashboard.


    ## Rate Limiting

    API requests are rate limited to ensure fair usage. The current limits are:

    - 100 requests per minute for standard endpoints

    - 1000 requests per minute for streaming endpoints


    ## Error Handling

    The API uses standard HTTP status codes and returns detailed error messages
    in the response body.
  version: 1.0-beta
  license:
    name: MIT
    url: https://opensource.org/licenses/MIT
servers:
  - url: http://localhost:8080
    description: Development
  - url: https://api.open.cx
    description: Production
security:
  - bearerAuth: []
paths:
  /phone/web-calls/{callId}/connect:
    post:
      tags:
        - Phone
      summary: Start a connected app voice call
      description: >-
        SDK call. Authorize with the call controlToken, after publishing
        microphone audio. Repeated activation does not start another call.
      operationId: connectWebCall
      parameters:
        - 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)$
          in: path
          name: callId
          required: true
      responses:
        '200':
          description: Default Response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/WebCallSuccessDto'
        '500':
          description: Internal Server Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorDto'
components:
  schemas:
    WebCallSuccessDto:
      $schema: https://json-schema.org/draft/2020-12/schema
      $id: '#/components/schemas/WebCallSuccessDto'
      type: object
      properties:
        success:
          type: boolean
      required:
        - success
      additionalProperties: false
    ErrorDto:
      type: object
      properties:
        statusCode:
          type: integer
        message:
          type: string
        error:
          type: string
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT

````

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