A GNKG seat is $200.
Metaphy LLC (Temecula, CA) sells one GNKG seat for $200 plus applicable tax. The seller is Metaphy LLC — not Google, and not the Chrome Web Store. NotebookLM and Gemini Notebook are trademarks of Google LLC; GNKG is an independent project.
Extension, console, and the agent harness
One seat covers one person’s GNKG use: the Chrome extension, the web console, and the MCP bridge plus harness files that ship with access. It is not a Google One or Gemini subscription.
Stripe checkout
Buy opens a Stripe-hosted checkout page. You enter your card details there, never on this static site and never in the extension.
14 days
Email logan@metaphysicsandcomputing.com within 14 days of purchase for a full refund of the seat fee. The Chrome Web Store does not process this payment and cannot refund it.
How licensing works
Free install, a key unlocks it
You install GNKG from the Chrome Web Store for free. A license key from Metaphy LLC unlocks the extension and the bridge; without one they stay locked and say so.
One Chrome profile per key
A key works on one Chrome profile at a time. Activating it on a second profile is refused with a message that the license is already active on another installation. While you are online, you can deactivate a profile to move your seat.
About once a week, online
The extension checks in with our license server about once a week and gets a fresh signed token. It keeps that token and a fingerprint of your key, not the key itself.
Up to 7 days of grace
If a check is missed because you are offline, GNKG keeps working for up to 7 more days. After that it asks you to reconnect: “Reconnect to refresh the license.”
Chrome 137 or newer
License tokens are checked with Chrome’s built-in cryptography, which needs Chrome 137 or newer.
What it does not stop
The license check stops casual use and sharing of keys. It does not stop someone who edits their own unpacked copy of the extension.
The Chrome Web Store listing, when it exists, is a separate public, free install path so the extension has a stable ID and auto-update. Paying for a seat is a purchase from Metaphy LLC. Google is not the seller, not the merchant of record, and not a party to the refund.
Your notebooks, now with a work ethic.
GNKG turns every Gemini Notebook into a small knowledge graph that your agents can read, extend and order around. As of 2.3.0 it also survives its own browser trying to kill it mid-sentence.
Upgraded in 2.3.0. Broken six times on purpose before release. Passed the tests that mattered.
Three parts, one bridge
Chrome extension
An MV3 extension that speaks Gemini Notebook's own RPC calls from your signed-in tab. No scraping, no API key you don't have. A side-panel console, a 3D graph viewer, and a DOM reader for the days Google moves the furniture.
MCP bridge
@metaphyllc/gnkg-bridge: MCP over stdio and Streamable HTTP at /mcp, a local socket the extension connects to, and a plain JSON twin for anything that can POST.
Agent harness
One-line installers that wire GNKG into Claude Desktop, Claude Code, Cursor, Windsurf and Codex, plus a /gnkg skill, an OpenAPI file, llms.txt, and Python and JS clients.
Ask a question. Then try to stop it.
Long grounded answers take minutes, and Chrome likes to recycle extension workers whenever it feels like it. Before 2.3.0, a long ask could die at about four minutes and hand back nothing. Pick a disaster and watch what the lane does now.
The timings are illustrative, compressed for your patience. The behaviour matches the shipping ask lane, and the receipts below are real.
Six tests. Four failures. We kept all of them.
One team broke it, another fixed it, and nobody graded their own work. Every row comes from the raw job record.
| Test | Fix in place | What we did | Result | Answer | Lesson |
|---|---|---|---|---|---|
| 1 | none yet | Long synthesis ask | failed | 0 chars · 256 s | The in-page fetch dies at about four minutes. |
| 2 | turn recovery | Same ask, with turn recovery | "done", empty | 0 chars · 290 s | A blank answer must never be called done. Now it's E_EMPTY_ANSWER. |
| 3 | empty is a failure | Same ask | lost | 0 chars · 170 s | The worker restarted mid-ask. It failed loudly, at least. |
| 4 | resume after restart | Same ask, left alone | done | 28,265 chars · 137 s | A clean stream works end to end, marker on the last line. |
| 5 | resume after restart | Stopped the worker at +61 s | E_EMPTY_ANSWER | 0 chars · 468 s | The stop killed the ask before Google saved a turn. Waiting can't fix that. |
| 6 | one re-ask | Stopped the worker at +61 s | done · reask | 31,846 chars · 257 s | One re-ask, attempts = 2, the right marker, nothing invented. |
It forms an orderly queue. Like a civilised bridge.
Every ask is a job keyed on caller, notebook, question and source set. Asks for one notebook take turns. Asks for different notebooks run at the same time. An agent that retries in a panic gets its own job back instead of a duplicate.
Measured: a second caller on the same notebook started at the exact millisecond the first ended. One caller in two notebooks ran both at once, overlapping by 26.9 s, with no answer leaking into the other.
Every tool, and what it's for
Feeding a whole codebase to a notebook
Notebook sources cap out around 500k words, so the pump weighs your files (code counts heavier than prose), splits anything over 400k at structural boundaries, packs the pieces first-fit-decreasing into 450k-word bins, and adds Bin 0 as a master index. Each bin goes in as a text source and is polled until it's ready. Edit the files and watch it repack.
Plug it into whatever you have
MCP, stdio
npx -y @metaphyllc/gnkg-bridgeFor Claude Code, Claude Desktop, Cursor, Windsurf and Codex. If two hosts both launch it, the second one attaches to the first instead of fighting over the port.
MCP, HTTP
/mcp · /openapi.json · /llms.txtStreamable HTTP for agents that live elsewhere, with a tunnel guide for cloud agents.
REST twin
one JSON POST per toolEvery tool as a plain JSON request on your own machine. Good for scripts, cron jobs and anything allergic to protocols.
Web console
the Console pageLive with the extension installed, or a built-in simulator without it. Includes the CosmicGraph 3D viewer.
Side panel
extension → Open consoleNotebooks and sources side by side, the same 3D graph, and a HUD that turns green once the session is captured.
Locked by default
GNKG_TOKEN · --lanLoopback only unless you say otherwise. LAN mode refuses to start without a token. The worker-stop test route only exists on loopback with its flag set.
What we won't pretend
- GNKG drives Gemini Notebook through the same calls its own web page makes. Google hasn't documented them, so they can change. A drift check catches that, and a page-reading fallback keeps you working meanwhile.
- A re-asked answer is a second answer to the same question from the same sources. It isn't a replay of the first attempt.
- Everything runs from your own signed-in browser and your own machine. GNKG never sees your Google password.
“The bridge was never the server. The bridge was the session.”