# Sign up (`mttr_signup`)

Updated October 24, 2026.

## What does mttr_signup do?

Signs you up with your email and answers your key. It is the one call that works before there is a key, so your assistant can do it without you leaving the chat. Anyone may make this call, before there is a key.

Who may call it: No key.

## When to use it

- Your assistant is connected to mttr but has no key yet.
- You want to start from the assistant rather than the website.

## What you ask

You might say: “Sign me up for mttr with you@example.com.”

```
mttr_signup({ email: "you@example.com" })
```

| Argument | Type | Needed | What it is |
| --- | --- | --- | --- |
| `email` | Text | Yes | The person's email address. |

## What comes back

- Your key, shown once. Keep it where your assistant can read it.
- The command that connects your assistant again with the key.
- What the key reaches: any public site’s report at once, and your own site’s private parts once you claim it.

A sample, with made-up sites and figures:

1. Email given
2. Key made (here)
3. Connected with the key
4. Site claimed

Your key starts mk_ and is shown once. Connect again with it, then claim your site.

## Over HTTP

```
curl https://mttr.si/mcp \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "mttr_signup",
      "arguments": {
        "email": "you@example.com"
      }
    }
  }'
```

## Sources

- [Model Context Protocol: tools](https://modelcontextprotocol.io/specification/2025-06-18/server/tools), Model Context Protocol: How an assistant calls a tool.

The call in full: [mttr_signup in the API reference](https://mttr.si/docs/reference#mttr_signup).

## Goes with

- [Claim a site](https://mttr.si/docs/tools/claim.md)
- [Brief](https://mttr.si/docs/tools/brief.md)