Agentic Browser

A standalone MCP server that gives any MCP client (Codex, Claude, etc.) browser automation via Playwright. Drive a real, already-logged-in Chrome through the Chrome DevTools Protocol — share cookies and sessions across agents.

Originally extracted from the pi coding agent's browser extension, now a standalone server so Codex / pi / any MCP client can all use the same browser.

Features

• 11 tools: browser_session, browser_navigate, browser_snapshot, browser_click, browser_type, browser_eval, browser_storage, browser_console, browser_wait_human, browser_screenshot, browser_close
• Two session modes:
  • real — connectOverCDP to an existing Chrome on port 9222 (reuse your logged-in profile: cookies, sessions, 2FA)
  • isolated — launchPersistentContext with an independent profile (headed/headless)
• Auto-launch Chrome: if port 9222 is down, the server spawns your Chrome starter script and waits for it — no manual browser launch needed.
• Stable element targeting: snapshot returns an ARIA accessibility tree (YAML); click/type target by role + name — no fragile ref/snapshot layers.
• Transports: stdio (default, for Codex-style spawn) and http (stateless streamable, --transport http --port 9223).

Requirements

• Node.js ≥ 18
• Playwright-compatible Chrome/Chromium installed (google-chrome-stable works)
• For real mode: a Chrome instance running with --remote-debugging-port=9222 and a dedicated user-data-dir (see Start Chrome with CDP)

Install

git clone https://github.com/q35888/agentic-browser-mcp.git
cd agentic-browser-mcp
npm install

Configure your MCP client

Codex (~/.codex/config.toml)

[mcp_servers.agentic-browser]
type = "stdio"
command = "/usr/bin/node"
args = [ "/path/to/agentic-browser-mcp/index.mjs" ]

Any MCP client (stdio)

Spawn node /path/to/agentic-browser-mcp/index.mjs over stdio — standard MCP initialize → tools/list → tools/call.

HTTP mode (long-running single instance)

node index.mjs --transport http --port 9223
# POST MCP requests to http://127.0.0.1:9223/mcp

Start Chrome with CDP (for real mode)

Chrome 150+ requires a non-default user-data-dir for remote debugging. Example starter script:

#!/usr/bin/env bash
PROFILE="$HOME/.agentic-browser-chrome-profile"
mkdir -p "$PROFILE"
# Fill in graphics session env if spawning from a non-graphical context
export XDG_RUNTIME_DIR="${XDG_RUNTIME_DIR:-/run/user/$(id -u)}"
export WAYLAND_DISPLAY="${WAYLAND_DISPLAY:-wayland-0}"
exec google-chrome-stable \
  --remote-debugging-port=9222 \
  --user-data-dir="$PROFILE" \
  --ozone-platform=wayland \
  "$@"

--ozone-platform=wayland is important when Chrome is spawned from a background process: otherwise Chrome's platform heuristic picks X11 and fails with Missing X server / Authorization required. Adjust for your display server (X11 users: drop the flag and ensure DISPLAY/XAUTHORITY are set).

If you don't start Chrome manually, the server will try to launch $HOME/.pi/agent/start-agent-chrome.sh automatically (override CHROME_STARTER in index.mjs to point at your own script).

Tools

Tool	Description
browser_session	Start/switch a session (real / isolated, headless, incognito). No args = ensure default real.
browser_navigate	Open a URL.
browser_snapshot	Return the page's ARIA tree (YAML). Use role+name for click/type.
browser_click	Click an element by role (+name).
browser_type	Fill an input by role (+name).
browser_eval	Run a JS expression in the page (read DOM/storage/fire requests).
browser_storage	Read cookies / localStorage / sessionStorage.
browser_console	Read buffered console logs (optional level filter).
browser_wait_human	For CAPTCHAs/manual steps — returns a prompt; the calling agent pauses and waits for the user.
browser_screenshot	Save a PNG to disk.
browser_close	Close the current session (real only disconnects CDP, never kills your Chrome).

Notes

• browser_wait_human: this server has no GUI/TUI. It returns a text prompt; the client agent is expected to surface it and wait for the user to reply.
• Session sharing: multiple MCP clients connecting to the same server share one Playwright session (and thus one Chrome). Tool calls are serialized to prevent races.
• Resource cleanup: on stdin EOF, transport close, or SIGINT/SIGTERM, the server disposes the session (with a 3s timeout fallback) — isolated browsers won't be orphaned.

License

MIT