chrome-cookies-mcp

An MCP (Model Context Protocol) server that reads cookies for a specified domain from a running Chrome instance, via the Chrome DevTools Protocol (CDP).

It returns cookies already decrypted by Chrome (no SQLite decryption, no App-Bound-Encryption handling), in cookies.txt (Netscape), JSON, or Cookie:-header format.

How it relates to the "Get cookies.txt LOCALLY" extension

That extension uses the privileged chrome.cookies.getAll({ domain }) API, which only works inside an extension. A standalone MCP server can't call it, so this project gets the same decrypted cookies a different way: it attaches to Chrome over CDP and calls Storage.getCookies, then applies the same domain-matching and the same Netscape/JSON/header serialization the extension used.

Requirement: launch Chrome with a debug port

CDP only works against a Chrome started with --remote-debugging-port. Chrome allows just one process per profile directory, so if your normal Chrome is already running you must close it first, then relaunch with the flag (still your real profile, same logins/cookies):

chrome.exe --remote-debugging-port=9222 \
  --user-data-dir="C:\Users\<you>\AppData\Local\Google\Chrome\User Data" \
  --profile-directory=Default \
  --remote-allow-origins=*

Helper:

npm run launch-chrome      # close your main Chrome first

Verify the port is live: open http://127.0.0.1:9222/json/version.

Install

npm install
cp .env.example .env.local   # then edit .env.local for your machine

Local configuration (.env.local)

Machine-specific settings (paths, port, profile) live in .env.local, which is gitignored and never committed. Copy .env.example to .env.local and edit. Values already set in the real environment — or in an MCP client's env block — override the file, so the same code runs unchanged on any machine.

Environment variables:

Var	Default	Meaning
CHROME_CDP_HOST	127.0.0.1	CDP host
CHROME_CDP_PORT	9222	CDP remote-debugging port
CHROME_PATH	auto-detected	chrome.exe path (launcher only)
CHROME_USER_DATA_DIR	OS default profile dir	profile dir (launcher only)
CHROME_PROFILE	Default	profile name (launcher only)

Run

npm start

Tools

get_cookies

Get cookies for a domain.

• domain (required): "example.com", ".github.com", or a full URL like "https://example.com/path".
• format: netscape | json | header (default json).
• name (optional): only the cookie with this exact name.
• path (optional): only cookies with this exact path.

Domain matching follows chrome.cookies.getAll: the query matches a cookie whose host equals the domain or is a sub/parent-domain of it.

list_domains

List all distinct cookie domains in the running Chrome with counts.

• filter (optional): case-insensitive substring of the domain name.

Register with an MCP client

Example (claude / Claude Code .mcp.json style):

{
  "mcpServers": {
    "chrome-cookies": {
      "command": "node",
      "args": ["/absolute/path/to/chrome-cookies-mcp/src/index.mjs"],
      "env": { "CHROME_CDP_PORT": "9222" }
    }
  }
}

Test

npm run launch-chrome           # or launch any Chrome with --remote-debugging-port=9333
CHROME_CDP_PORT=9333 node test/smoke.mjs

Security note

This server exposes your browser's cookies — including session tokens — to any MCP client connected to it. Cookies are sensitive credentials. Run it only locally and only with clients you trust. The CDP debug port itself is also a powerful local interface; do not expose it beyond 127.0.0.1.