Licensing

agent-browser-shield is source-available under the PolyForm Shield 1.0.0 license. The source is public and you can read, fork, modify, distribute, and use it commercially — the carve-out is that you can't use it to build a product that competes with agent-browser-shield itself or with any PixieBrix product that's built on top of it.

What's allowed for free

PolyForm Shield permits use for any purpose, including commercial use, with one exception (see What requires a commercial license). That covers, for example:

• Personal use: research, experiment, study, hobby projects.
• Internal use at a for-profit company — including incorporating it into internal tooling that supports revenue-generating activity.
• Embedding it inside a product or service whose value comes from something other than agent-browsing protection (e.g., a SaaS app that uses agent-browser-shield to harden its own agentic workflows).
• Use by charities, educational institutions, nonprofits, and government.

If your use falls in any of these buckets, you don't need to talk to us.

What requires a commercial license

You need a separate commercial license from PixieBrix, Inc. if you want to provide a product that competes with agent-browser-shield or with any PixieBrix product built on top of it. Under PolyForm Shield, "competes" is interpreted broadly: a competing product can be a service, library, plug-in, port to a different platform or language, or even a free offering — what matters is whether it's marketed as a practical substitute for the software or for one of PixieBrix's products that uses it.

Concretely, that means you need a commercial license to:

• Sell, host, or otherwise offer a product whose core value is browser-agent shielding/redaction/preprocessing for end users or developers.
• Repackage or rebrand agent-browser-shield (or a derivative) as your own agent-protection product.
• Build a competitor to a PixieBrix commercial offering that incorporates agent-browser-shield.

If you're not sure whether your use is competing, please ask — it's faster and cheaper than guessing wrong.

How to obtain a commercial license

Email support@pixiebrix.com with:

• Your company and a brief description of the intended use.
• Approximate scale (number of seats, number of agents, deployment model).
• Whether you need indemnification, warranty, or support terms.

We respond within 5 business days.

Contributions

By submitting a pull request to this repository, you agree to the terms of PixieBrix's Contributor License Agreement (CLA). Sign once via the CLA form — see CONTRIBUTING.md for details.

The CLA grants PixieBrix the right to relicense your contribution — including under commercial terms — which is what lets us sell commercial licenses to would-be competitors while keeping the project source-available for everyone else. You retain copyright in your work.

Dependencies

The dependencies that agent-browser-shield builds on are licensed permissively (Apache 2.0, MIT, BSD, ISC) and remain under their own terms. The combined work — agent-browser-shield plus its dependencies — is bound by PolyForm Shield because of this project's license, not because of theirs.

Why not Apache 2.0 or MIT?

Permissive OSS licenses are great for adoption but they don't give us a way to fund continued development of agent-browser-shield against well-resourced competitors who could fork it and ship a rival product. PolyForm Shield keeps the source open and freely usable — including by commercial users — while reserving the right to ship a competing agent-protection product for PixieBrix's commercial customers. If you'd like to argue for a different license, please open an issue — we're listening.