> ## Documentation Index
> Fetch the complete documentation index at: https://cofounder.appeeky.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Company Brain Sync

> Keep external knowledge sources (Notion pages or any URL) continuously ingested into the knowledge base, re-ingesting only on change.

# Company Brain Sync

The [knowledge base](/concepts/knowledge-base) can ingest a Notion page or URL on
demand, but a one-time import goes stale the moment the source is edited. Company
Brain Sync keeps chosen sources fresh: a daily job re-pulls each and
re-ingests **only when the content changed**, superseding the previous
snapshot so the brain reflects the *current* doc — not a pile of old versions.

## Difference from library documents

The [library](/capabilities/library) is knowledge you **author inside the app**
— your source of truth, injected as raw document context. Sync is for knowledge
whose canonical copy lives **elsewhere** (Notion, a public URL): you edit it
there, and the brain mirrors + distills it into memory facts, auto-refreshing on
change. If you author everything in the library, you don't need sync.

## How it works

1. You subscribe a Notion page for syncing.
2. Each day the sync job re-reads the page and hashes its content.
3. If the hash is unchanged → nothing happens (no wasted ingest).
4. If it changed → the previous knowledge source is superseded and the new
   content is re-ingested through the normal pipeline (distilled into pending
   memory facts you can approve in the [Vault](/concepts/vault)).

Source kinds today: **Notion pages** and **any URL** (web page / public doc).
Slack channels are planned. The registry is source-agnostic — adding a new kind
only needs a reader.

## Setup

**Settings → Company Brain sync.** Paste any URL and hit **Add URL**, or (with
[Notion](/integrations/notion) connected) search your Notion pages and add them.
Toggle sources on/off, remove them, or hit **Sync now** to run immediately.

## API

```
GET    /v1/cofounder/knowledge/sync            # list synced sources
POST   /v1/cofounder/knowledge/sync            # { kind: "url", externalId: "https://…" }
                                               # or { kind: "notion", externalId: pageId, title }
PATCH  /v1/cofounder/knowledge/sync/:id        # { enabled }
DELETE /v1/cofounder/knowledge/sync/:id
POST   /v1/cofounder/knowledge/sync/run        # sync now (this owner)
```

Browse pages to add via `GET /v1/cofounder/memory/notion/pages`.

## See also

* [Knowledge Base](/concepts/knowledge-base) — how ingested knowledge is used
* [Notion](/integrations/notion) — connecting Notion
* [Second Brain](/capabilities/second-brain) — the on-demand ingest side