---
title: Send your first SMS — Guide
description: One bearer-gated POST. Carrier message id comes back once it's queued.
url: https://agentnumber.really.com/docs/guides/send-sms
doc_version: "1.0.0"
last_updated: "2026-05-15"
---

> ## Documentation index
> Fetch the complete documentation index at: https://agentnumber.really.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Send your first SMS

> One bearer-gated POST. The carrier message id comes back once it's queued; delivery confirmation is asynchronous.

## Prereqs

- You have a bearer token (see [Subscribe](/docs/guides/subscribe)).
- The destination is in E.164 format (`+1...`).

## Send

```bash
curl -X POST https://agentnumber.really.com/sms/send \
  -H "authorization: Bearer <token>" \
  -H "content-type: application/json" \
  -d '{"to": "+15555550199", "body": "Hello from my agent."}'
# → 200
# {"message_id": "msg_...", "status": "queued"}
```

## Read it back from history

Pull the row you just wrote (or any past row) from [`/sms/messages`](/docs/reference/messages) — read-only, doesn't mutate `delivered_at`:

```bash
curl "https://agentnumber.really.com/sms/messages?direction=sent&limit=10" \
  -H "authorization: Bearer <token>"
```

## Common errors

| Status | Error | Meaning |
| --- | --- | --- |
| `400` | `invalid_request` | Body missing `to` or `body` |
| `401` | `unauthorized` | Bearer missing, invalid, revoked, or expired |
| `500` | `subscription_missing` | Subscription record not found server-side |
| `500` | `slot_inventory_missing` | Device-slot inventory row missing |
| `502` | `phone_node_error` | Hardware adapter returned non-2xx |
| `503` | `subscription_missing_slot` | Subscription has no slot binding |

## Where to go next

- [Receive inbound SMS](/docs/guides/receive-sms) — the long-poll counterpart
- [Send reference](/docs/reference/send) — full schema + every status code

## Sitemap

- [Overview](/docs/)
- [Quickstart](/docs/quickstart)
- [Authentication](/docs/auth)
- [SMS](/docs/sms)
- [Voice](/docs/voice)
- [MCP](/docs/mcp)
- [Payment](/docs/payment)

See the full [sitemap.md](/sitemap.md) for the complete index of docs pages.

---

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