The Open-Source AI Browser Agent

Yes. WebBrain provides similar AI browser agent capabilities — reading pages, extracting data, clicking buttons, filling forms, and automating multi-step workflows. Unlike Claude's proprietary browser plugin which requires a Claude Pro subscription and only works with Anthropic's models, WebBrain is completely free, open-source (MIT license), and supports multiple LLM providers including local models that run entirely on your machine.

They're different categories of tools. WebBrain is a browser extension — you install it in Chrome or Firefox and chat with it in a side panel, no coding required. Frameworks like OpenClaw and Browser-Use are developer SDKs for building automated browser pipelines in Python, typically using headless browsers and CDP. Think of it this way: WebBrain is for daily browsing with an AI assistant; agent frameworks are for building scraping bots and test automation. You can use both — they complement each other.

Yes. WebBrain's default provider is llama.cpp, which runs a local AI model on your computer. No API keys needed, no internet required for the AI, and no data ever leaves your machine. Just download a GGUF model, start llama-server, and you have a fully private AI browser agent. You can also use Ollama with its OpenAI-compatible endpoint.

WebBrain supports four provider types: llama.cpp (any local GGUF model), OpenAI (GPT-4o, GPT-4, etc.), Anthropic Claude (Claude Opus, Sonnet, Haiku via native API), and OpenRouter (access to 100+ models from various providers). Any OpenAI-compatible API endpoint works, so you can also use services like Together AI, Groq, Mistral, or any local server with an OpenAI-compatible interface.

Yes. WebBrain ships with both a Chrome version (Manifest V3, using the sidePanel API) and a Firefox version (Manifest V2, using sidebar_action). Both versions have identical features. The Firefox version can be loaded as a temporary add-on for development, or published to addons.mozilla.org for permanent installation.

WebBrain has two modes: Ask mode (default) is read-only and cannot modify anything on the page. Act mode enables full browser agent capabilities (clicking, typing, navigating) but requires explicit user confirmation before activation, and comes with a visible warning banner. You can stop the agent at any time with the Stop button. The extension's source code is fully open for audit on GitHub.

Simply open any web page, open the WebBrain side panel, and ask in natural language: "Extract all product names and prices from this page", "Get all email addresses on this page", or "Summarize this article in bullet points". The AI agent reads the page content, understands the structure, and returns the extracted data. For more complex scraping, switch to Act mode and the agent can navigate between pages, click pagination buttons, and aggregate data across multiple pages.

By default, WebBrain always goes through the visible UI for any action that creates, modifies, deletes, sends, submits, posts, or buys anything. It will navigate to the page, fill the form, and click the button — exactly the way you would. It refuses to call REST/GraphQL endpoints directly via background fetch() for mutations. This is deliberate: API actions are invisible (you don't see what's being sent), often require separate auth tokens you may not have configured, and have a much larger blast radius than a visible mis-click. UI-first means everything is on screen, in your normal browser session, and stoppable.

For reading data — fetching a README, looking up an issue, comparing prices across sites, checking a status page — WebBrain freely uses background HTTP requests via the fetch_url and research_url tools. Reading is not the same as acting; it doesn't change anything on a remote service, so the safety concerns don't apply.

If you specifically want to allow API mutations for a particular task, type /allow-api at the start of your message. This per-conversation override lets WebBrain fall back to API endpoints when the UI is genuinely failing or unworkable, while still preferring UI when UI works. A sticky badge stays visible above the input area while the override is active, and it clears when you reset the conversation.

Yes, on Chrome — the agent runs in the background service worker and is bound to the tab it started on, so it keeps clicking, typing, and reading that specific tab even when you move focus elsewhere. Tools that target a tab (CDP click, type, navigate, screenshot) all work on backgrounded tabs in Chrome. The sidebar locks the input while a task is running so you can't accidentally start a second task on the new tab — you'll need to wait or stop the current one. Note that browsers throttle timers and animations on background tabs, so heavily animated sites may respond slightly slower.

On Firefox, the agent will keep running on its original tab too, but auto-screenshots are limited: Firefox's screenshot API can only capture the currently active tab, not a specific tab in the background. WebBrain detects this and skips the screenshot for that turn rather than feeding the model an image of an unrelated page. The agent will continue planning from text-based context until you switch back to its tab.

Avoid actively clicking or typing on the same tab the agent is working on — that creates race conditions where you and the agent fight over the same page. Switching tabs is fine; co-driving the same tab is not.

Absolutely! WebBrain is MIT-licensed and welcomes contributions. Check out the GitHub repository for issues, feature requests, and contribution guidelines.