# StablePhone Make AI Phone Call

> StablePhone Make AI Phone Call is a paid API for AI agents from stablephone.dev, paid per call via x402, $0.54/call, status unknown (last checked 2026-09-15).

Initiates an AI-driven outbound phone call to a specified number with a given task, returning a call_id for tracking

## Facts

- Endpoint: POST https://stablephone.dev/api/call
- Price: $0.54/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/stablephone-f57f7b80
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1k-QE00Wgi5SC3VSoA0RG

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 stablephone-f57f7b80 -d '<json body>'
```

Example prompt: Call +1-415-555-0123 and ask them if they have availability for a haircut tomorrow at 2pm — leave my name as Alex if they ask.

## When to prefer this

Use this endpoint when an AI agent needs to autonomously place a real outbound voice call to a phone number with a specific task or instruction. Ideal for automating calls to businesses, scheduling, inquiries, or any scenario requiring voice interaction without human intervention. Prefer over SMS or messaging endpoints when voice is required.

## Known failure modes

- Invalid or unroutable phone number — call fails to connect
- Insufficient USDC balance or x402 payment failure — call not initiated
- Malformed task description — AI may not execute intended behavior
- Rate limiting or provider-side errors — HTTP 429 or 500
- Number blocked or rejected by carrier — call dropped

## How this service works

Make a call

## Output

Returns a call_id (string) that can be used to poll for call status and transcript via the status endpoint. The call itself is executed asynchronously by an AI agent.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "from": {
   "type": "string",
   "pattern": "^\\+1\\d{10}$"
  },
  "task": {
   "type": "string",
   "maxLength": 4000,
   "minLength": 1
  },
  "model": {
   "enum": [
    "base",
    "turbo"
   ],
   "type": "string"
  },
  "voice": {
   "type": "string"
  },
  "record": {
   "type": "boolean"
  },
  "metadata": {
   "type": "object",
   "propertyNames": {
    "type": "string"
   },
   "additionalProperties": {}
  },
  "max_duration": {
   "type": "integer",
   "maximum": 30,
   "minimum": 1
  },
  "phone_number": {
   "type": "string",
   "pattern": "^\\+1\\d{10}$"
  },
  "first_sentence": {
   "type": "string",
   "maxLength": 500
  },
  "voicemail_action": {
   "enum": [
    "hangup",
    "leave_message",
    "ignore"
   ],
   "type": "string"
  },
  "voicemail_message": {
   "type": "string",
   "maxLength": 500
  },
  "wait_for_greeting": {
   "type": "boolean"
  },
  "transfer_phone_number": {
   "type": "string"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/stablephone-f57f7b80/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from stablephone.dev](https://www.zero.xyz/host/stablephone.dev/llms.txt)