Exnos MCP server

Exnos

Live browser-state verification for AI coding agents.

Your AI says "done." Exnos is how it knows.

One tool call returns the full state of the Chrome tab you're looking at: every field, every button, every console error, network requests, storage, performance—in milliseconds. Read-only. Local. Free and open source.

By GOL Productions.

The Problem

AI coding agents edit files and hope for the best. When something breaks:

You: "The button doesn't work"
AI:  "Can you check the console for errors?"
You: "It says TypeError something something"
AI:  "Can you paste the full error?"

Back and forth. Slow. Frustrating.

The Solution

You: "The button doesn't work"
AI:  [calls exnos_verify]
AI:  "Console shows 'TypeError: handleClick is not defined' at line 47.
      The handler was renamed to onClick. Fixing now."

Exnos gives your AI eyes. It sees what you see—instantly.

Install

npx @golproductions/exnos@latest setup

That's it. Detects Claude Code, Cursor, and Windsurf—registers with all of them, opens the extension folder, tells you to load it in Chrome. Takes 30 seconds.

Manual install

1. Connect your agent

{ "mcpServers": { "exnos": { "command": "npx", "args": ["@golproductions/exnos"] } } }

Or for Claude Code:

claude mcp add --scope user exnos -- npx @golproductions/exnos

2. Load the extension

npx @golproductions/exnos@latest path

Open chrome://extensions → Developer mode → Load unpacked → select that folder.

Badge reads ON when connected.

What It Sees

Tools

exnos_verify parameters

Selector deep-dive

Pass selector to get:

• selectorText — inner text content
• selectorVisible — actually visible?
• selectorBounds — {top, left, width, height}
• selectorHTML — outer HTML
• selectorStyles — computed: color, backgroundColor, fontSize, fontWeight, fontFamily, padding, margin, border, zIndex, overflow, transform, transition

CLI

npx @golproductions/exnos@latest setup       # configure everything
npx @golproductions/exnos@latest uninstall   # remove everything Exnos added (run it in each project where you ran init)
npx @golproductions/exnos@latest path        # extension folder path
npx @golproductions/exnos@latest init        # write rules to agent config
npx @golproductions/exnos@latest rules       # print rule text

Architecture

Shortened. The full README is on GitHub.