---
title: "Keyless Buy Number"
method: POST
path: "/v1/x402/numbers/buy"
tags: ["x402 Keyless"]
---

# Keyless Buy Number

`POST /v1/x402/numbers/buy`

## Request

- Base URL: `https://api.agentline.cloud`
- URL: `https://api.agentline.cloud/v1/x402/numbers/buy`
- Auth: none declared

Buy a US number for $3 from prepaid balance, with a 30-day lease.

## Request body

- KeylessBuyBody
  - `agent_name` string, nullable: Display name for the voice agent
  - `system_prompt` string, nullable: Personality/behavior instructions spoken on ALL calls
  - `initial_greeting` string, nullable: Opening line spoken when a call connects
  - `voice_id` string, nullable: TTS voice preset (e.g. 'female-1') or a voice UUID
  - `transfer_number` string, nullable: Must be the owner phone. Live transfers dial only owner_phone.
  - `voicemail_message` string, nullable: Message left if the call goes to voicemail
  - `owner_phone` string, nullable: Owner's E.164 phone. Calls from it enter task mode, and it is the only live-call transfer destination.
  - `country` string: Country code (only 'US' supported)
  - `number_type` string: 'local' or 'tollfree'
  - `area_code` string, nullable: Preferred 3-digit US area code

## Response `200`

Successful Response

- unknown

## Other responses

- `401`: Agent access token required
- `422`: Validation Error

---

[API](https://skmtc.dev/agentline/apis/agentline-prepaid-phone-service-for-ai-agents.md) · [All operations](https://skmtc.dev/agentline/apis/agentline-prepaid-phone-service-for-ai-agents/llms.txt) · [OpenAPI document](https://skmtc.dev/agentline/apis/agentline-prepaid-phone-service-for-ai-agents/revisions/18c0bdbb4b30?raw)