# Your site’s content brain (`mttr_content_brain`)

Updated October 24, 2026.

## What does mttr_content_brain do?

What mttr knows about a site you claimed, as files to keep in its repository: what the business does and where, how its pages read, the facts its structured data states, what is worth writing, and every brief so far. A key may make this call on the sites it has claimed.

Who may call it: Your claimed sites.

## When to use it

- Before you or your assistant write any page for the site.
- After a read, to see what changed in it.

## What you ask

You might say: “Get the content brain for my site and save it in the repo.”

```
mttr_content_brain({ site: "example.com" })
```

| Argument | Type | Needed | What it is |
| --- | --- | --- | --- |
| `site` | Text | Yes | The site, as a domain such as example.com. |

## What comes back

- Five files for .mttr/brain/: positioning, voice, proof, gaps and a log.
- What is missing, said in words, when mttr has not read it yet.

A sample, with made-up sites and figures:

| File | Holds |
| --- | --- |
| positioning.md | Line of work, kind, where |
| voice.md | Sentences near 14 words, speaks as "we" |
| proof.md | Serves Cicero, Liverpool (from /) |
| gaps.md | sump pump repair (search) |
| log.md | No briefs yet |

## Over HTTP

```
curl "https://mttr.si/api/v1/account/content/brain?site=example.com" \
  -H "Authorization: Bearer $MTTR_KEY"
```

## When it fails

| When | Status | What to do |
| --- | --- | --- |
| Your assistant has no key yet | 401 over MCP | Sign up with `mttr_signup`, then connect again with the key it gives. |

## 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_content_brain in the API reference](https://mttr.si/docs/reference#mttr_content_brain).

## Goes with

- [The next page to write](https://mttr.si/docs/tools/content-next.md)
- [Your work board](https://mttr.si/docs/tools/todo.md)