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

# Attach SIP Endpoint

> Attach SIP configuration to a given phone number. You can attach inbound, outbound, or both directions. Outbound will automatically include SIP endpoint configuration.



## OpenAPI

````yaml post /sip/attach
openapi: 3.0.0
info:
  title: ClearTalk API
  description: The ClearTalk API Documentation
  version: '1.0'
  contact:
    name: Developer Support
    email: devsupport@cleartalk.ai
servers:
  - url: https://api.cleartalk.ai
    description: ClearTalk AI API Server
security: []
tags: []
paths:
  /sip/attach:
    post:
      tags:
        - sip
      summary: Attach SIP Endpoint
      description: >-
        Attach SIP configuration to a given phone number. You can attach
        inbound, outbound, or both directions. Outbound will automatically
        include SIP endpoint configuration.
      operationId: SIPController_attach
      parameters: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AttachPhoneNumberDto'
      responses:
        '201':
          description: SIP endpoint attached successfully.
        '400':
          description: Invalid phone number or direction.
        '401':
          description: Unauthorized or missing API token.
      security:
        - apiKey: []
components:
  schemas:
    AttachPhoneNumberDto:
      type: object
      properties:
        phone_number:
          type: string
          example: '+14444444477'
          description: Phone number in E.164 format (must include country code)
        direction:
          type: string
          description: SIP direction to attach
          enum:
            - inbound
            - outbound
            - both
          example: both
        sip_region:
          type: string
          description: Region for SIP endpoint
          enum:
            - US1 (Oregon)
            - EU1 (Ireland)
            - ASIA1 (Sydney)
          example: US1 (Oregon)
      required:
        - phone_number
        - direction
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: x-api-key
      description: API Key for authentication

````