# History

Known keeps every version of every page and records who made each change. You can see what a page said at any point in the past and what changed in a wiki over time.

## Changes and revisions

Each write to a wiki creates a change. A change has a number, an author, a message, and a time. A single change can affect several pages, for example when you move a page with the pages under it. Each page the change affects gets a new revision.

Records keep a separate history. For tables, Known keeps every version of each row. See [Records](https://known.info/docs/records).

## Authors

Every change records its author:

| Author | Shown as |
|---|---|
| A person | Their name, and where they made the change: the browser, the CLI, or a site. |
| A connected agent | The agent and the person it acted for, for example "Claude for Ana". |
| The Known assistant | The assistant and the person who asked, for example "Known assistant for Ana". |

Page history can't be deleted, by people or by agents.

## View history in the browser

To see a page's revisions, open the page and click **History**. Select a revision to see what it changed. Changed lines are highlighted, along with any changes to the title, path, or metadata.

To see every change in a wiki, click **Changes**.

## View history with the CLI

```
known acme wiki history general:handbook.onboarding
known acme wiki diff general:handbook.onboarding
known acme wiki changes general:
known acme wiki changes general:handbook
```

| Command | Shows |
|---|---|
| `wiki history` | A page's revisions, newest first. |
| `wiki diff` | What the latest revision changed. Add `--change <id>` or `--revision <id>` for an earlier one. |
| `wiki changes` | Every change in a wiki, or under one page, newest first. |

## Read a page as it was

To read a page or a wiki's tree at a point in the past, pass `--at` with a time or `--change` with a change number:

```
known acme wiki read general:handbook.onboarding --at 2026-09-01T00:00:00Z
known acme wiki tree general: --change 3120
```

To read a table as it was, use `wiki records --at <time>`.

## FAQ

### How far back can I see history?

On the Free plan, you can see the last 90 days. Older history is kept and becomes visible when you upgrade. See [Plans and limits](https://known.info/docs/plans).

### Can history be deleted?

Page history can't be deleted. Records can lose old versions if the page sets a retention limit. See [Schemas and retention](https://known.info/docs/schemas).