# AgentPhone SMS Message Send

> AgentPhone SMS Message Send is a paid API for AI agents from AgentPhone at mpp.orthogonal.com, paid per call via MPP, $0.03/call, not verified (last probed 2026-10-10); live alternatives: Spraay SMS Payment Notification ($0.02) and PaySponge Textbelt SMS Send ($0.02).

Agents call it through Zero, which pays per call: no API key and no wallet of your own. New accounts start with $5.

Live alternatives for the same use case:
- [Spraay SMS Payment Notification](https://www.zero.xyz/c/spraay-sms-payment-notification-2b2f41dd) ($0.02)
- [PaySponge Textbelt SMS Send](https://www.zero.xyz/c/paysponge-textbelt-sms-send-702ae420) ($0.02)

Send an outbound SMS message from an AI agent's provisioned phone number to a recipient, with first-message compliance requirements.

## Facts

- Endpoint: POST https://mpp.orthogonal.com/agentphone/v1/messages?utm_source=zero.xyz
- Price: $0.03/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-10
- Last successful call: 2026-07-11
- Success rate: 17% of calls made through Zero
- Activations on Zero: 6
- Provider: AgentPhone
- Docs: https://api.agentphone.ai
- Website: https://api.agentphone.ai
- Tags: phone, voice, sms, calls, social
- Canonical page: https://www.zero.xyz/c/agentphone-sms-message-send-37193417
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kXoGFJbV8fow-OOVane8p

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 agentphone-sms-message-send-37193417 -d '<json body>'
```

Example prompt: Send an SMS from my AgentPhone number to +15551234567 saying: 'Hi, this is Bloom Coffee. Reply STOP to opt out. Your order is ready for pickup!' — make sure it includes the opt-in disclosure since it's our first message to this contact.

## When to prefer this

Use this endpoint when an AI agent needs to send outbound SMS to a human contact using a real US/Canada phone number provisioned via AgentPhone. Prefer this over email or push notification when SMS delivery is required. This is the right choice when the agent already has a provisioned number (via the Numbers endpoint) and needs to initiate or continue a text conversation, especially for notifications, alerts, or customer outreach workflows.

## Known failure modes

- Missing first-message compliance text (brand name or opt-out) causes rejection
- Invalid or unprovisioned sender phone number returns 400 or 403 error
- Recipient number in unsupported region or invalid format
- Message body exceeds SMS character limits
- Insufficient USDC balance or unpaid account returns payment error
- Rate limiting if too many messages sent in short succession

## How this service works

Send an SMS from an agent's phone number. First message compliance: Your initial SMS to any new contact must include (1) your brand name, (2) opt-in confirmation, and (3) opt-out instructions (e.g., "Reply STOP to unsubscribe"). Non-compliant first messages may be silently filtered by carriers.

## Output

Returns a delivery confirmation including a message ID, delivery status, timestamp, and the sending phone number. Confirms whether the message was queued or sent successfully.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentphone-sms-message-send-37193417/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mpp.orthogonal.com](https://www.zero.xyz/host/mpp.orthogonal.com/llms.txt)