Privacy

Last updated 24 July 2026.

Glass Box is a language model that runs in your browser. The short version: the demo doesn’t need an account, doesn’t send your text anywhere, and doesn’t track you.

What happens without an account

Nothing leaves your device. The model weights are downloaded once as part of the page, and every guess, every attention weight, and every training step is computed locally in your browser. Your prompts are never transmitted to us, because there is no server-side model to transmit them to.

If you train your own model with “Start from nothing”, those weights exist only in that browser tab. Close the tab and they’re gone. They are never uploaded.

What happens if you sign in

Signing in is optional and buys you exactly one thing: saving a run. We use GitHub OAuth, and we ask GitHub for the read:user and user:email scopes. From that we store:

• Your GitHub username, avatar URL, and primary verified email address
• A session record so you stay signed in
• Any runs you explicitly choose to save — the prompt, temperature, dice seed, generated text, and the loss curve if you trained your own model

We never receive your GitHub password, and we cannot write to your repositories or read anything private. A run is only ever saved when you press the save button.

Where it’s stored

Account and run data live on onejsonfile.com, the Birch Tree Studio storage service. The site is hosted on Vercel, which processes standard web-server request logs.

What we don’t do

• No analytics, no tracking pixels, no advertising identifiers
• No third-party cookies — the only cookie is your own session
• No selling or sharing of data with anyone
• No training on your prompts (the model is fixed and shipped with the page)

Deleting your data

You can delete any saved run from your runs page. To delete your account and everything attached to it, email us from the support page and we’ll remove it.

Glass Box is part of Birch Tree Studio. Questions about this policy go to the support page.