# Read it again (`mttr_rescan`)

Updated October 24, 2026.

## What does mttr_rescan do?

Asks mttr to read a site again after it has been changed. It answers a job to watch. A site is read at most once every ten minutes. Any key may make this call, on any public site.

Who may call it: Any key.

## When to use it

- A fix is published and you want to see it count.

## What you ask

You might say: “I published the fixes. Read example.com again.”

```
mttr_rescan({ site: "example.com", reason: "Rewrote the service pages" })
```

| Argument | Type | Needed | What it is |
| --- | --- | --- | --- |
| `site` | Text | Yes | The site, as a domain such as example.com. |
| `reason` | Text | No | What was changed, in a few words. |

## What comes back

- A job, with how many reads are ahead of it.
- When asked too soon, when it may be asked again.

A sample, with made-up sites and figures:

1. Waiting (here)
2. Running
3. Done

Job j_318 is in line. 2 reads ahead of it.

## Over HTTP

```
curl -X POST "https://mttr.si/api/v1/sites/example.com/rescan" \
  -H "Authorization: Bearer $MTTR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"reason":"Rewrote the service pages"}'
```

## 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. |
| The site is on a private address, or cannot be read | 400 | The answer says “mttr cannot read example.com:” and why. Check the domain. |
| The site was read in the last ten minutes | 429 | The answer gives `allowedAt`. Ask again after it. |
| The site was removed from mttr | 403 | Nothing: a removed site is not read. |

## 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_rescan in the API reference](https://mttr.si/docs/reference#mttr_rescan).

## Goes with

- [Where a read stands](https://mttr.si/docs/tools/job.md)
- [What changed](https://mttr.si/docs/tools/changes.md)