> ## 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.

# List Providers

> List telephony provider accounts linked to your account. Supports Twilio and SIP Trunk providers.



## OpenAPI

````yaml 2026-03-01/api.yml GET /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:
    get:
      tags:
        - Providers
      summary: List Providers
      description: >-
        List telephony provider accounts linked to your account. Supports Twilio
        and SIP Trunk providers.
      operationId: providers_list
      parameters:
        - $ref: '#/components/parameters/CartesiaVersionHeader'
        - name: type
          in: query
          description: Filter by provider type.
          required: false
          schema:
            type: string
            enum:
              - twilio
              - sip_trunk
        - name: account_sid
          in: query
          description: Filter by account SID (Twilio providers only).
          required: false
          schema:
            type: string
      responses:
        '200':
          description: ''
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/ProviderAccountResponse'
      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'
        default: '2026-03-01'
        enum:
          - '2026-03-01'
  schemas:
    ProviderAccountResponse:
      title: Provider Account
      description: A telephony provider account.
      oneOf:
        - $ref: '#/components/schemas/TwilioProviderResponse'
        - $ref: '#/components/schemas/SIPTrunkProviderResponse'
      discriminator:
        propertyName: type
        mapping:
          twilio:
            $ref: '#/components/schemas/TwilioProviderResponse'
          sip_trunk:
            $ref: '#/components/schemas/SIPTrunkProviderResponse'
    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'
        label:
          type: string
          nullable: true
          description: A human-readable label for the provider.
      required:
        - type
        - id
        - account_sid
        - api_key_sid
        - region
    SIPTrunkProviderResponse:
      title: SIP Trunk
      type: object
      description: A linked SIP trunk provider.
      properties:
        type:
          type: string
          enum:
            - sip_trunk
          description: Always `"sip_trunk"`.
        id:
          type: string
          description: Unique identifier for the provider.
        label:
          type: string
          nullable: true
          description: A human-readable label for the provider.
        inbound:
          description: Inbound configuration. Present when inbound is configured.
          allOf:
            - $ref: '#/components/schemas/SIPTrunkInboundDetails'
        outbound:
          description: Outbound configuration. Present when outbound is configured.
          allOf:
            - $ref: '#/components/schemas/SIPTrunkOutboundDetails'
      required:
        - type
        - id
    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
    SIPTrunkInboundDetails:
      title: SIPTrunkInboundDetails
      type: object
      description: >-
        Inbound SIP configuration. Passwords are never returned; only the
        configured username is exposed as `auth_username`.
      properties:
        allowed_addresses:
          type: array
          items:
            type: string
          description: Source IP addresses or CIDR ranges allowed to send SIP traffic.
        allowed_numbers:
          type: array
          items:
            type: string
          description: Caller numbers allowed on inbound calls.
        auth_username:
          type: string
          description: SIP username returned without the password.
        media_encryption:
          description: Media encryption policy. Defaults to `allowed`.
          allOf:
            - $ref: '#/components/schemas/SIPMediaEncryption'
      required:
        - allowed_addresses
        - allowed_numbers
        - auth_username
        - media_encryption
    SIPTrunkOutboundDetails:
      title: SIPTrunkOutboundDetails
      type: object
      description: >-
        Outbound SIP configuration. Passwords are never returned; only the
        configured username is exposed as `auth_username`.
      properties:
        address:
          type: string
          description: SIP server hostname or address used for outbound signaling.
        destination_country:
          type: string
          description: >-
            Two-letter ISO 3166-1 alpha-2 destination country code, or an empty
            string if not set.
        transport:
          $ref: '#/components/schemas/SIPTrunkTransport'
        media_encryption:
          description: Media encryption policy. Defaults to `disabled`.
          allOf:
            - $ref: '#/components/schemas/SIPMediaEncryption'
        auth_username:
          type: string
          description: SIP username returned without the password.
      required:
        - address
        - transport
        - media_encryption
        - auth_username
    SIPMediaEncryption:
      title: SIPMediaEncryption
      type: string
      enum:
        - disabled
        - allowed
        - required
      description: >-
        SRTP policy for call audio. `disabled` does not negotiate encryption,
        `allowed` uses encryption when available, and `required` rejects calls
        that cannot use encryption.
    SIPTrunkTransport:
      title: SIPTrunkTransport
      type: string
      enum:
        - tcp
        - tls
      description: Transport for outbound SIP signaling.
  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).
      x-default: $CARTESIA_API_KEY

````