●  V1.0.0 — PRODUCTION RELEASE  ●

Give Your AI Agent

a Real Browser

Relay for AI Agents connects Claude, Cursor, Cline, and any MCP-compatible AI to a real, logged-in browser — a live Chromium tab. Navigate, click, fill forms, intercept network traffic, run JavaScript all from your agent.

AI Agent Hoststdio MCP ServerWebSocket Browser ExtensionLive Chromium Tab

BROWSER TOOLS

17 Tools. Every Interaction Your Agent Needs.

From reading the DOM to intercepting network requests full-stack browser access out of the box, grouped across 6 categories.

Tab Management

Open, close, and switch tabs. Agent-controlled tabs are grouped separately from your own browsing.

tabs_context_mcp

 tabs_create_mcp

tabs_close_mcp

Input & Interaction

Click, hover, type, scroll, key presses, wait everything a human does, your agent does too.

computer

 click-by-ref  hover

Page Reading

Full accessibility tree, plain text extraction, CSS and text search. Know exactly what is on screen.

read_page

get_page_text  find

Form Handling

Fill inputs, select dropdowns, upload files. Handle any form your agent encounters at scale.

form_input

 select_option  file_upload

Window Control

Resize the viewport for responsive testing, precise screenshots, or breakpoint-specific scraping.

resize_window  navigate

DevTools Access

Read console logs, intercept network requests, execute JavaScript directly in the page context.

read_console_messages

read_network_requests

javascript_tool

ARCHITECTURE

Built for the Real World.

No single point of failure. Multi-session. Multi-browser. 128-bit token authentication.

Self-electing Broker

First MCP server to bind the port becomes broker. Others connect as relays. Broker takeover on exit with no interruption.

Multi-session

Multiple agent sessions can drive the same browser simultaneously. Popup shows all sessions with broker and relay badges.

Multi-browser

Register N MCP entries on different ports for N separately-controlled browsers. Each appears as distinct tool prefixes.

128-bit Token Auth

Bearer tokens via crypto.randomBytes. Required for non-loopback hosts. Pair with Tailscale for full transport encryption.

COMPATIBILITY

One Tool. Every Agent Ecosystem.

Relay speaks stdio MCP fully host-agnostic. Works locally on the same machine, or remotely over Tailscale.

Cursoropencode Continue.dev Claude DesktopCline (VS Code) OpenAI Codex CLI LangChain / CrewAI Custom MCP Agents

QUICK INSTALL

Up in Under 2 Minutes.

One installer script handles Claude Desktop, Cursor, and more. The extension popup turns green within seconds of restart.

# Local setup — browser on the same machine
node install.mjs

# Remote setup — generates a token, prints next steps
node install.mjs --remote
# Load the extension in Chrome or Edge
chrome://extensions → Developer mode → Load unpacked → extension/

Prerequisites: Node.js 18+, Chrome or Edge, any supported MCP host.

Full guide at docs/install-and-usage.pdf covers Microsoft Store Claude Desktop, Tailscale, multi-browser, and troubleshooting.

Network Isolation

Plain WebSocket never expose port 9876 to the internet. Always pair remote setups with Tailscale or a private overlay network.

Token Rotation

128-bit hex tokens via crypto.randomBytes. CLI refuses non-loopback hosts without a token. Rotate when sharing access ends.

Session Binding

Lock the extension to a specific session ID. Tool calls from any other session are rejected at the broker level automatically.

Your Agent Needs a Real Browser

Free, open source, MIT licensed. Built by Let’s Set You Up.
Relay v1.0.0 is available now on GitHub and Microsoft Edge

Coming Soon on Chrome

FAQ: Your AI Agent and a Real, Logged-In Browser

Does Relay use my logged-in browser?

Yes. Relay attaches to your real, logged-in browser, so your AI agent works inside your existing session with cookies and authentication intact. There is no headless browser to re-authenticate and no bot detection to fight, so your agent can act on sites that normally block automation.

How is a logged-in browser different from Playwright MCP?

Playwright and Puppeteer launch a fresh headless browser with no session, so agents fail on anything behind a login. Relay's logged-in browser lets your agent work on Gmail, LinkedIn, internal dashboards, or any authenticated site immediately, using the session you already have open.

Which AI agents work with Relay?

Relay speaks standard MCP, so it works with Claude Desktop, Cursor, Cline, Codex CLI, and any MCP-compatible host. Run it locally on the same machine or remotely over a private Tailscale network, all through your real, logged-in browser.