History Sync

A Chrome extension + small server that turns your browsing history into something your AI agents can query.

You install the extension. It captures pages you dwell on for 10+ seconds. Captured pages land on a server you trust (hosted or your own). Then you point Claude, Cursor, Claude Desktop, or any other MCP-capable client at that server and ask what you've been reading.

Status: friends-and-family alpha. Submitted to the Chrome Web Store; review pending. Until it's approved, install in developer mode (below).

Two ways to run it

⚠ Data is stored in plaintext at rest. No end-to-end encryption yet (v2 territory). On the hosted version, the operator can see your captures the same way they can see anything on their own Postgres. If your browsing includes things you wouldn't share with a single trusted operator, self-host. Even self-hosted, data is plaintext in your Postgres — keep that server private.

What never gets captured, in either mode: incognito tabs, chrome:// pages, extension internals, form contents, passwords, cookies, page-body text beyond title + meta tags, sites matching your disallow list.

The full privacy policy is at history-sync.vercel.app/privacy.

Install the extension (developer mode)

Until the Web Store approval lands, install from source:

git clone https://github.com/bradthebeeble/history-sync
cd history-sync
pnpm install
pnpm --filter @history-sync/extension build

Then in Chrome (or any Chromium browser — Comet, Brave, etc.):

1. Open chrome://extensions
2. Toggle Developer mode on (top-right)
3. Click Load unpacked
4. Pick apps/extension/.output/chrome-mv3/
5. The History Sync icon appears in your toolbar — pin it for convenience

Note for self-hosters: if you also want the extension to talk to your own Google OAuth client (instead of the bake-time hosted one), rebuild with your client ID:

VITE_GOOGLE_CLIENT_ID=<your-client-id>.apps.googleusercontent.com \
VITE_SERVER_URL=https://<your-server> \
  pnpm --filter @history-sync/extension build

Then add https://<extension-id>.chromiumapp.org/ as an authorized redirect URI on that Google OAuth client (the extension shows you the exact ID and URL on first sign-in attempt).

Connect the extension

Open the popup, click Sign in with Google, finish the consent flow.

• Hosted users: that's it — the extension is now syncing to history-sync.vercel.app.
• Self-hosters: expand the Server chip at the top of the popup, paste your server URL (e.g. http://localhost:3000), save (the popup will sign you out), then sign in again — this time against your server.

The popup shows queue depth and last-sync timestamp so you can see capture working.

Connect your AI agent

The extension is the data pipe in. The MCP server is the data pipe out — for any agent that speaks Model Context Protocol over Streamable HTTP. Five tools are exposed:

Endpoint URLs

Authentication

Hosted (Stytch OAuth): the MCP client does the dance for you — it'll register itself via Dynamic Client Registration, open a consent screen in your browser, and store the resulting OAuth tokens. Most modern clients (Claude.ai, Claude Desktop, Cursor, MCP Inspector) handle this transparently when you just give them the URL.

Self-host (static token): sign in to your /grants page, click Generate token, give it a label like "Claude Desktop", copy the raw value (shown once). Then configure your client to send it as Authorization: Bearer <token>.

Client-specific setup

npx -y @modelcontextprotocol/inspector

curl -s "$URL" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{}}'

Try it

Once your client is connected, just ask:

What blog posts did I read about Rust this week?

Top 10 domains I visited yesterday?

What was that LangChain GitHub issue I had open on Tuesday?

Disallow rules

Anything you don't want captured or stored — add a pattern:

• Web app: /disallow — *.bank.com, mail.google.com, secret-project.notion.so
• Extension popup: same — and a one-click "Block this site" button for the current tab

Pattern matches are retroactive: adding *.bank.com deletes any prior matching entries from the server, not just future ones.

Build it yourself / contribute

pnpm install
pnpm db:up                  # Postgres 16 in Docker
pnpm -r typecheck           # workspace-wide tsc

Useful scripts:

Default local Postgres URL (matches docker-compose.yml):

postgresql://history_sync:history_sync_dev@localhost:5432/history_sync

Docs

• Self-hosting guide — docs/SELF_HOSTING.md
• Privacy policy — history-sync.vercel.app/privacy
• Deployment notes (Vercel + Neon) — docs/deployment.md

License

MIT.