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 are looking at: every field, every button, every console error, network requests, storage, performance, in milliseconds. Read-only. Local. Free, MIT.

Experimental. Exnos reads a live Chrome tab through a local bridge. Expect it to break when a site ships a change. MIT licensed, as-is, no warranty.

Install (2 minutes)

1. Connect your agent

claude mcp add-json --scope user exnos '{"command":"npx","args":["@golproductions/exnos"]}'

Any MCP client (.mcp.json):

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

2. Load the extension

npx @golproductions/exnos path

Open chrome://extensions, enable Developer mode, click Load unpacked, pick that folder. Badge reads ON when connected.

What it sees

A single exnos_verify call returns:

URL, title, ready state -- navigation facts, not assumptions
Every visible field with its live value
Every button with its disabled state
Checkboxes and radios with checked state
Visible alerts and UI warnings
Console errors and uncaught exceptions captured from page load
Network requests -- every fetch and XHR: URL, method, status, response body, timing. Failures surfaced first.
WebSocket frames -- sent and received, last 30
localStorage, sessionStorage, cookies -- live storage state
Performance -- page load, TTFB, DOM ready, paint timing, long tasks, JS heap
Focus -- which element has focus right now
Shadow DOM -- pierces component library boundaries
Same-origin iframes -- text and errors inside frames
App globals -- any window.__* values the app sets

Tools

Tool	What it returns
`exnos_verify`	Full live state. Optional `tab` (URL/title substring) targets another tab. Optional `selector` deep-dives one element: text, visibility, computed styles, HTML. Optional `includeHidden` includes off-screen elements.
`exnos_tabs`	All open tabs: title, URL, active state.

CLI

npx @golproductions/exnos path     # print extension folder path
npx @golproductions/exnos init     # write Exnos rule into agent rules files
npx @golproductions/exnos rules    # print the rule text

Notes

Server on 127.0.0.1:17872 (override: EXNOS_PORT). GET / returns {"exnos":true,"extension":true|false}.
Extension reconnects automatically after Chrome or server restart.
Internal pages (chrome://) cannot be inspected.
Console errors are captured from document_start. Pages open before the extension loaded need one reload.
Network tap intercepts fetch and XHR at document_start. Requests made before the extension loaded are not captured.

License

MIT. The names "Exnos" and "GOL Productions" are trademarks of GOL Productions and are not licensed under MIT. Forks must use a different name.

Product · GOL Productions · GitHub