# AgentLine Voice Call API

> AgentLine Voice Call API is a paid API for AI agents from api.agentline.cloud, paid per call via x402, $0.5/call, status unknown (last checked 2026-09-15).

Initiates an outbound phone call from a wallet-owned AI agent number to a destination number, billed per call via x402 crypto payment

## Facts

- Endpoint: POST https://api.agentline.cloud/v1/x402/calls
- Price: $0.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentline-voice-call-api-1a0f4d23
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wZ2ul7JAWhyHqYacahhM9

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agentline-voice-call-api-1a0f4d23 -d '<json body>'
```

Example prompt: Call +14155550199 from my AgentLine number +12125551234 and handle the conversation.

## When to prefer this

Choose this endpoint when an AI agent needs to autonomously initiate an outbound voice call to a real phone number using a dedicated agent-owned number, especially when crypto (USDC) micropayment billing via x402 is preferred and no traditional telecom account setup is desired.

## Known failure modes

- Invalid E.164 format for to_number or from_number returns validation error
- Insufficient USDC balance or x402 payment failure prevents call initiation
- from_number not associated with the caller's wallet returns authorization error
- Destination number unreachable or invalid returns call failed status
- Rate limits exceeded returns 429 or equivalent throttling error

## How this service works

Get a real phone number for your AI agent in under 10 minutes. Works with OpenClaw, Hermes Agent, and any LLM. Outbound calls, SMS, and inbound voice — one API. No telecom experience needed.

## Output

Returns a call session object including call ID and status indicating whether the outbound call was successfully initiated between the from_number and to_number.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "to_number",
  "from_number"
 ],
 "properties": {
  "to_number": {
   "type": "string",
   "description": "Destination phone number in E.164 format"
  },
  "from_number": {
   "type": "string",
   "description": "Your wallet-owned number (E.164, e.g. '+12125551234')"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "id": {
   "type": "string"
  },
  "status": {
   "type": "string"
  },
  "tx_hash": {
   "type": "string"
  },
  "to_number": {
   "type": "string"
  },
  "from_number": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentline-voice-call-api-1a0f4d23/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.agentline.cloud](https://www.zero.xyz/host/api.agentline.cloud/llms.txt)