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

# Create Provider

> Link a telephony provider account



## OpenAPI

````yaml /latest.yml POST /agents/phone-numbers/providers
openapi: 3.0.1
info:
  title: Cartesia API
  version: 0.0.1
servers:
  - url: https://api.cartesia.ai
    description: Production
security: []
paths:
  /agents/phone-numbers/providers:
    post:
      tags:
        - Providers
      summary: Create Provider
      description: Link a telephony provider account
      operationId: providers_create
      parameters:
        - $ref: '#/components/parameters/CartesiaVersionHeader'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateProviderBody'
      responses:
        '201':
          description: Provider created.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ProviderAccountResponse'
        '400':
          description: Invalid credentials.
        '409':
          description: >-
            Provider already exists for this account and region. Use PATCH to
            update credentials.
      security:
        - APIKeyAuth: []
components:
  parameters:
    CartesiaVersionHeader:
      name: Cartesia-Version
      in: header
      description: API version header.
      required: true
      schema:
        type: string
        format: date
        example: '2026-03-01'
        enum:
          - '2026-03-01'
  schemas:
    CreateProviderBody:
      title: Create Provider
      description: |-
        Request body for linking a telephony provider. Discriminated by `type`.
        **Twilio**:
          - Credentials are validated against Twilio before the provider is created
          - Each account SID + region combination can only be linked once
      oneOf:
        - $ref: '#/components/schemas/CreateTwilioProviderBody'
      discriminator:
        propertyName: type
        mapping:
          twilio:
            $ref: '#/components/schemas/CreateTwilioProviderBody'
    ProviderAccountResponse:
      title: Provider Account
      description: A telephony provider account.
      oneOf:
        - $ref: '#/components/schemas/TwilioProviderResponse'
      discriminator:
        propertyName: type
        mapping:
          twilio:
            $ref: '#/components/schemas/TwilioProviderResponse'
    CreateTwilioProviderBody:
      title: Twilio
      type: object
      properties:
        type:
          type: string
          enum:
            - twilio
          description: Must be `"twilio"`.
        account_sid:
          type: string
          description: Your Twilio account SID.
        api_key_sid:
          type: string
          description: A Twilio API key SID.
        api_key_secret:
          type: string
          description: The corresponding API key secret.
        region:
          $ref: '#/components/schemas/TelephonyRegion'
          default: us1
      required:
        - type
        - account_sid
        - api_key_sid
        - api_key_secret
    TwilioProviderResponse:
      title: Twilio
      type: object
      description: >-
        A linked Twilio account. The `api_key_sid` field is partially masked in
        responses.
      properties:
        type:
          type: string
          enum:
            - twilio
          description: Always `"twilio"`.
        id:
          type: string
          description: Unique identifier for the provider.
        account_sid:
          type: string
          description: The Twilio account SID.
        api_key_sid:
          type: string
          description: The Twilio API key SID (partially masked).
        region:
          $ref: '#/components/schemas/TelephonyRegion'
      required:
        - type
        - id
        - account_sid
        - api_key_sid
        - region
    TelephonyRegion:
      title: TelephonyRegion
      type: string
      enum:
        - us1
        - ie1
        - au1
      description: >-
        The Twilio region the phone number and API key are configured for. `us1`
        (US), `ie1` (Ireland), `au1` (Australia). Default is `us1`.
      default: us1
  securitySchemes:
    APIKeyAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key
      description: >-
        Cartesia API key (`sk_car_...`). Get one at
        [play.cartesia.ai/keys](https://play.cartesia.ai/keys).

````