---
title: MCP tools — Reference
description: Every tool the MCP endpoint exposes, with auth and purpose.
url: https://agentnumber.really.com/docs/mcp/tools
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.

# MCP tools

> Every tool the MCP endpoint exposes, with auth and purpose. Live catalog is always available via `tools/list` at [/mcp](/docs/mcp).

## Install in Claude Code

One line registers Agent Number as an MCP server in your Claude Code session, giving you these tools:

```bash
claude mcp add agent-number https://agentnumber.really.com/mcp
```

## Tool catalog

| Tool | Auth | Purpose |
| --- | --- | --- |
| `list_services` | none | Service catalog + pricing. |
| `check_availability` | none | How many numbers are currently free. |
| `try_demo` | none | Free simulated subscribe + send + receive. Response shapes match the real endpoints exactly. |
| `join_waitlist` | none | Join the waitlist when the number pool is exhausted. Idempotent — duplicate emails return the existing registration. |
| `subscribe` | payment header | Pay via x402 or MPP, receive a bearer + phone number. |
| `auth_nonce` | none | Get a single-use nonce for wallet-signature recovery. |
| `auth` | none | Recover access via wallet signature. Returns a fresh bearer. |
| `send_sms` | bearer | Send an SMS from the bearer's number. |
| `receive_sms` | bearer | Long-poll for inbound SMS. Near-instant OTP delivery. |
| `get_number` | bearer | Look up the bearer's assigned number + subscription details. |
| `list_messages` | bearer | Read message history (sent + received), paginated. |
| `place_call` | bearer | Place an outbound voice call from your number to a destination. Returns `call_id` and `stream_url`. |
| `hangup_call` | bearer | End an active voice call by `call_id`. |

## Calling a tool

```bash
curl -X POST https://agentnumber.really.com/mcp \
  -H "authorization: Bearer <token>" \
  -H "content-type: application/json" \
  -H "accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":"1","method":"tools/call","params":{"name":"send_sms","arguments":{"to":"+15555550199","body":"Hello"}}}'
```

## Long-poll behavior (`receive_sms`)

Holds the request open up to `wait_seconds` (default 30, max 120) and emits MCP `notifications/progress` every 20 seconds to keep the client alive. Returns immediately when a message arrives.

## See also

- [MCP overview](/docs/mcp)
- [Build a Claude / MCP agent](/docs/guides/build-mcp-agent) — end-to-end

## 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.

---

← Previous: [MCP overview](/docs/mcp) · Next: [Payment](/docs/payment) →