Retell AI Get Phone Number API

openapi: 3.0.3
info:
  title: Retell SDK Add Community Voice Get Phone Number API
  version: 3.0.0
  contact:
    name: Retell Support
    url: https://www.retellai.com/
    email: support@retellai.com
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0.html
servers:
- url: https://api.retellai.com
  description: The production server.
security:
- api_key: []
tags:
- name: Get Phone Number
paths:
  /get-phone-number/{phone_number}:
    get:
      description: Retrieve details of a specific phone number
      operationId: getPhoneNumber
      parameters:
      - in: path
        name: phone_number
        schema:
          type: string
          minLength: 1
          example: '+14157774444'
        required: true
        description: E.164 format of the number (+country code, then number with no space, no special characters), used as the unique identifier for phone number APIs.
      responses:
        '200':
          description: Successfully retrieved a phone number.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PhoneNumberResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/UnprocessableContent'
        '500':
          $ref: '#/components/responses/InternalServerError'
      tags:
      - Get Phone Number
components:
  schemas:
    AgentVersionReference:
      oneOf:
      - type: integer
        minimum: 0
        example: 1
      - type: string
        minLength: 1
        maxLength: 20
        pattern: ^[a-z0-9_-]+$
        example: prod
      description: Agent version reference. Supports a numeric version (for example 3) or a tag/environment name (for example "prod"). When a tag is provided, resolution uses that exact tag assignment (including its dynamic variables). If the tag exists but is currently unassigned, it resolves to latest. When a numeric version (or latest) is provided, resolution applies dynamic variables from the preferred tag for that resolved version (most recently assigned), if any.
    PhoneNumberResponse:
      type: object
      required:
      - phone_number
      - phone_number_type
      - last_modification_timestamp
      properties:
        phone_number:
          type: string
          example: '+14157774444'
          description: E.164 format of the number (+country code, then number with no space, no special characters), used as the unique identifier for phone number APIs.
        phone_number_type:
          type: string
          enum:
          - retell-twilio
          - retell-telnyx
          - custom
          example: retell-twilio
          description: Type of the phone number.
        phone_number_pretty:
          type: string
          example: +1 (415) 777-4444
          description: Pretty printed phone number, provided for your reference.
        allowed_inbound_country_list:
          type: array
          items:
            type: string
          example:
          - US
          - CA
          - GB
          description: List of ISO 3166-1 alpha-2 country codes from which inbound calls are allowed. If not set or empty, calls from all countries are allowed.
          nullable: true
        allowed_outbound_country_list:
          type: array
          items:
            type: string
          example:
          - US
          - CA
          description: List of ISO 3166-1 alpha-2 country codes to which outbound calls are allowed. If not set or empty, calls to all countries are allowed.
          nullable: true
        area_code:
          type: integer
          example: 415
          description: Area code of the number to obtain. Format is a 3 digit integer. Currently only supports US area code.
        inbound_agents:
          type: array
          items:
            $ref: '#/components/schemas/AgentWeight'
          description: Inbound agents to bind to the number with weights. If set and non-empty, one agent will be picked randomly for each inbound call, with probability proportional to the weight. Total weights must add up to 1.
          nullable: true
        outbound_agents:
          type: array
          items:
            $ref: '#/components/schemas/AgentWeight'
          description: Outbound agents to bind to the number with weights. If set and non-empty, one agent will be picked randomly for each outbound call, with probability proportional to the weight. Total weights must add up to 1.
          nullable: true
        inbound_sms_agents:
          type: array
          items:
            $ref: '#/components/schemas/AgentWeight'
          description: Inbound SMS agents to bind to the number with weights. If set and non-empty, one agent will be picked randomly for each inbound SMS, with probability proportional to the weight. Total weights must add up to 1. If not set or empty, fallback to inbound_sms_agent_id.
          nullable: true
        outbound_sms_agents:
          type: array
          items:
            $ref: '#/components/schemas/AgentWeight'
          description: Outbound SMS agents to bind to the number with weights. If set and non-empty, one agent will be picked randomly for each outbound SMS, with probability proportional to the weight. Total weights must add up to 1. If not set or empty, fallback to outbound_sms_agent_id.
          nullable: true
        nickname:
          type: string
          example: Frontdesk Number
          description: Nickname of the number. This is for your reference only.
          nullable: true
        inbound_webhook_url:
          type: string
          example: https://example.com/inbound-webhook
          description: If set, will send a webhook for inbound calls, where you can to override agent id, set dynamic variables and other fields specific to that call.
          nullable: true
        inbound_sms_webhook_url:
          type: string
          example: https://example.com/inbound-sms-webhook
          description: If set, will send a webhook for inbound SMS, where you can override agent id, set dynamic variables and other fields specific to that chat.
          nullable: true
        last_modification_timestamp:
          type: integer
          example: 1703413636133
          description: Last modification timestamp (milliseconds since epoch). Either the time of last update or creation if no updates available.
        sip_outbound_trunk_config:
          type: object
          nullable: true
          properties:
            termination_uri:
              type: string
              example: someuri.pstn.twilio.com
              nullable: true
              description: The termination URI for the SIP trunk for the phone number.
            auth_username:
              type: string
              example: username
              nullable: true
              description: The username used for authenticating the SIP trunk for the phone number.
            transport:
              type: string
              example: TCP
              nullable: true
              description: Outbound transport protocol for the SIP trunk for the phone number. Valid values are "TLS", "TCP" and "UDP". Default is "TCP".
        fallback_number:
          type: string
          example: '+14155551234'
          description: Enterprise only. Phone number to transfer inbound calls to when organization is in outage mode. Can be either a Retell phone number or an external number. Cannot be the same as this phone number, and cannot be a number that already has its own fallback configured (prevents nested forwarding).
          nullable: true
    AgentWeight:
      type: object
      required:
      - agent_id
      - weight
      properties:
        agent_id:
          type: string
          minLength: 1
          example: oBeDLoLOeuAbiuaMFXRtDOLriTJ5tSxD
        agent_version:
          $ref: '#/components/schemas/AgentVersionReference'
        weight:
          type: number
          example: 0.5
          minimum: 0
          exclusiveMinimum: true
          maximum: 1
          description: The weight of the agent. When used in a list of agents, the total weights must add up to 1.
  responses:
    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            type: object
            properties:
              status:
                type: string
                enum:
                - error
              message:
                type: string
                example: API key is missing or invalid.
    BadRequest:
      description: Bad Request
      content:
        application/json:
          schema:
            type: object
            properties:
              status:
                type: string
                enum:
                - error
              message:
                type: string
                example: Invalid request format, please check API reference.
    UnprocessableContent:
      description: Unprocessable Content
      content:
        application/json:
          schema:
            type: object
            properties:
              status:
                type: string
                enum:
                - error
              message:
                type: string
                example: Cannot find requested asset under given api key.
    InternalServerError:
      description: Internal Server Error
      content:
        application/json:
          schema:
            type: object
            properties:
              status:
                type: string
                enum:
                - error
              message:
                type: string
                example: An unexpected server error occurred.
  securitySchemes:
    api_key:
      type: http
      scheme: bearer
      bearerFormat: string
      description: Authentication header containing API key (find it in dashboard). The format is "Bearer YOUR_API_KEY"