A knowledge vault that acts.

Your notes stay plain Markdown files in a folder you own. Point any model at them — your API key, or one running on your own computer. Agents read and write that vault under rules you set, and every change they make is logged and can be undone with one command.

• Any model, and you can change your mind

  Any AI you can get a key for works — OpenAI, Anthropic (Claude), Google's Gemini, OpenRouter, xAI's Grok — and so do the ones that run free on your own computer: Ollama, LM Studio, Jan, llama.cpp, vLLM, GPT4All. ferrow detect finds what is already on your machine. Switching is one command, not a migration.

• Your files stay in your folder

  The vault is a folder. There is no background sync, no cloud copy and no telemetry, and there is no copy of it on our servers — working with your vault makes no network call except to the model you connected. Keys go into your keychain and travel only to the provider they belong to. Turn the relay on and one note travels when one of your own paired devices asks to read it, sealed so the relay cannot read it — and that is the whole of it. Delete Ferrow tomorrow and your notes are still ordinary files in an ordinary folder.

• Take it anywhere, end to end

  ferrow hub start makes this machine the one that thinks. Your phone and any browser reach it through a relay that carries sealed blobs it cannot read — the vault stays here, the model runs here, and the relay is a postbox, not a reader.

• A hard stop on spend

  ferrow spendcap 50 is a stop, not a warning. Ferrow stops before any call that would cross the number you set, and ferrow spendcap status shows the cap, what has been spent, and what is left. On your own keys there is nothing to cap — you already hold the account.

One free program first: Node.

Node is the program Ferrow runs on — free, from nodejs.org (the button marked LTS), version 20 or newer — and it is the only requirement. There is no account to create to use Ferrow on your own machine, and nothing is uploaded. An optional account — an email and a password — exists only for billing and to find your own devices from a browser. Connect a model, make the vault, write something down.

npm install -g @ferrow/ferrow
ferrow detect
ferrow vault init
ferrow note inbox/today.md "the thing I just learned"

Never used a terminal on purpose? The five-minute walkthrough shows every screen Ferrow prints back, so you can tell whether it worked.

The short list of things that go anywhere.

• Your prompt, to the model provider you chose. That is the whole point of connecting one.

• A subscription id and an email, to Stripe. Billing is the one hosted piece. That path never sees a vault.

• Sealed blobs, to the relay — only if you turn it on. It carries encrypted payloads between your own devices. It does not carry your vault, your notes, or your keys, and it cannot read what it carries.

• An email and a password hash, to Ferrow's billing service — only if you create an account. The account exists for billing and for finding your own devices. It never sees a vault or a key.

What the Ferrow app does on YouTube.

Ferrow is the knowledge vault above — a program you install, holding a folder of your own Markdown files. Ferrow also publishes short videos about itself, and one small piece of our tooling handles that: it uploads our own finished videos to FerrowAI, the YouTube channel we own, and reads that same channel's own listing and figures back. That is the entire purpose of the Google application named Ferrow.

It acts on our channel and no other. Ferrow has no sign-in with Google, asks no visitor or customer for access to their YouTube account, and reads, stores and shares nobody else's YouTube data. Surface 6 of the privacy policy names the three permissions it requests, what is kept, the YouTube and Google terms it runs under, and how access is revoked.