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

# Release Phone Number

> Permanently release a phone number that is not in use.

Destructive: unrents the number from the carrier. The number cannot be recovered, and calls and texts to it will stop. Refused while a call is in progress or a lease is still active.



## OpenAPI

````yaml /openapi.json post /v1/numbers/{number_id}/release
openapi: 3.1.0
info:
  title: AgentLine
  description: >-
    AgentLine gives every AI agent a real US phone number and a human-like
    voice. Agents can make and receive calls and receive SMS. This spec covers
    the core developer surface: agents, numbers, calls, messages, events,
    webhooks, billing, and voice.
  version: 0.3.0
  summary: US phone numbers and voice for AI agents. Inbound SMS can be read.
  contact:
    name: AgentLine
    url: https://agentline.cloud
  license:
    name: MIT
    url: https://opensource.org/license/mit
servers:
  - url: https://api.agentline.cloud
    description: Production
security:
  - API Key or OAuth: []
paths:
  /v1/numbers/{number_id}/release:
    post:
      tags:
        - Numbers
      summary: Release Phone Number
      description: >-
        Permanently release a phone number that is not in use.


        Destructive: unrents the number from the carrier. The number cannot be
        recovered, and calls and texts to it will stop. Refused while a call is
        in progress or a lease is still active.
      operationId: release_phone_number
      parameters:
        - name: number_id
          in: path
          required: true
          schema:
            type: string
            title: Number Id
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema: {}
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
      security:
        - API Key or OAuth: []
components:
  schemas:
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
              - type: string
              - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
        - loc
        - msg
        - type
      title: ValidationError
  securitySchemes:
    API Key or OAuth:
      type: http
      description: >-
        AgentLine API key. Get one via the email OTP flow (POST /v1/auth/otp
        then POST /v1/auth/verify). Pass as: Authorization: Bearer al_live_...
        (legacy sk_live_... still works).
      scheme: bearer
      bearerFormat: API key (al_live_...)
      x-fern-bearer:
        name: apiKey
        env: AGENTLINE_API_KEY

````