Browser Bridge (BBX)

About

Browser Bridge connects your AI coding agent to the Chrome tab you already have open. Instead of starting from a clean headless context, the agent reads the real page - logged-in sessions, feature flags, SPA state, seeded storage - the way you'd read DevTools, but structured and token-efficient.

It returns DOM trees, computed styles, layout data, console logs, network requests, and storage as structured JSON. No screenshots needed, no raw HTML dumps. The agent can also interact with the page, apply reversible CSS and DOM patches, and visually confirm fixes - all scoped to your explicit session.


What it does:

• Query DOM by selector, ARIA role, or text - with depth and node budgets
• Read computed styles, box model, and layout for specific elements
• Access console output, network requests, browser storage, and performance metrics
• Evaluate JavaScript in the page context
• Click, type, scroll, navigate, wait for elements, fill and submit forms
• Apply scoped CSS overrides and DOM patches - all reversible, session-scoped
• Capture element or region screenshots for visual confirmation


When to use it:

• Debug a layout bug that only appears in a logged-in or feature-flagged state
• Verify a local code change actually rendered correctly in Chrome
• Patch live CSS to prove a fix, then port the minimal change back to source
• Inspect why a form won't submit - check disabled state, coverage, missing attributes, JS errors
• Read SPA client-side state (localStorage, sessionStorage) after a real user journey


Supported agents:

Compatible with any AI coding agent that supports the Model Context Protocol (MCP) or can run shell commands. Setup for all major agents is built into the extension's side panel. See the project README on GitHub for the full list and setup guides.


How it works:

The extension opens a native messaging channel to a local daemon on your machine. Your agent connects via MCP or the bbx CLI and sends structured requests. The extension executes each request in the active tab and returns only the data asked for - no page dumps.

Access is scoped to one explicitly enabled Chrome window. The agent targets the active tab by default. No ambient browser access. Patches are tracked per session and roll back cleanly.


Setup:

1. Install this extension from the Chrome Web Store
2. Run: `npm install -g @browserbridge/bbx`
3. In the side panel, set up MCP or CLI skill for your agent
4. Enable a Chrome window for agent access
5. Ask your agent to inspect or patch the current tab

Requires Chrome and Node.js on the same machine as your agent.


Privacy:

All data stays local - the extension communicates only with the companion daemon on your machine. No external servers, analytics, or cloud services. Sessions are explicit and patches don't persist across reloads. Your agent may forward results under its own policy; Browser Bridge itself only moves data between your browser and your local machine.

Open source - GitHub: github.com/koltyakov/browser-bridge