The Create Phone Number API from Retell AI — 1 operation(s) for create phone number.
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openapi: 3.2.0
info:
title: Retell SDK Create 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: Create Phone Number
paths:
/create-phone-number:
post:
description: Buy a new phone number & Bind agents
operationId: createPhoneNumber
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
inbound_agents:
type:
- array
- 'null'
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.
outbound_agents:
type:
- array
- 'null'
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.
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.
nickname:
type: string
example: Frontdesk Number
description: Nickname of the number. This is for your reference only.
inbound_webhook_url:
type:
- string
- 'null'
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.
allowed_inbound_country_list:
type:
- array
- 'null'
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.
allowed_outbound_country_list:
type:
- array
- 'null'
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.
number_provider:
type: string
enum:
- twilio
- telnyx
example: twilio
description: The provider to purchase the phone number from. Default to twilio.
country_code:
type: string
enum:
- US
- CA
example: US
description: The ISO 3166-1 alpha-2 country code of the number you are trying to purchase. If left empty, will default to "US".
toll_free:
type: boolean
description: Whether to purchase a toll-free number. Toll-free numbers incur higher costs.
phone_number:
type: string
minLength: 1
example: '+14157774444'
description: The number you are trying to purchase in E.164 format of the number (+country code then number with no space and no special characters).
transport:
type:
- string
- 'null'
example: TCP
description: Outbound transport protocol to use for the phone number. Valid values are "TLS", "TCP" and "UDP". Default is "TCP".
fallback_number:
type:
- string
- 'null'
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).
responses:
'201':
description: Successfully created a new number.
content:
application/json:
schema:
$ref: '#/components/schemas/PhoneNumberResponse'
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'500':
$ref: '#/components/responses/InternalServerError'
tags:
- Create Phone Number
summary: Create phone number
x-summary-source: derived
components:
responses:
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.
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.
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.
schemas:
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
maximum: 1
description: The weight of the agent. When used in a list of agents, the total weights must add up to 1.
exclusiveMinimum: 0
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
- 'null'
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.
allowed_outbound_country_list:
type:
- array
- 'null'
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.
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
- 'null'
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.
outbound_agents:
type:
- array
- 'null'
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.
inbound_sms_agents:
type:
- array
- 'null'
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.
outbound_sms_agents:
type:
- array
- 'null'
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.
nickname:
type:
- string
- 'null'
example: Frontdesk Number
description: Nickname of the number. This is for your reference only.
inbound_webhook_url:
type:
- string
- 'null'
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.
inbound_sms_webhook_url:
type:
- string
- 'null'
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.
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
- 'null'
properties:
termination_uri:
type:
- string
- 'null'
example: someuri.pstn.twilio.com
description: The termination URI for the SIP trunk for the phone number.
auth_username:
type:
- string
- 'null'
example: username
description: The username used for authenticating the SIP trunk for the phone number.
transport:
type:
- string
- 'null'
example: TCP
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
- 'null'
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).
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.
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"