- Add a shared helper for reading the built extension background bundle. - Skip the Firefox/WebExtension linter assertions when the generated bundle is absent. - Keep fresh checkouts able to run pytest without building gitignored artifacts first.
browser-cli
Control your real, running browser from the terminal or the Python SDK — no headless browser, no Playwright, no virtual display. Your actual open tabs, windows, and tab groups respond to your commands.
What it does
You have 40 tabs open. You want to close all the duplicates, group the GitHub ones, save your session before a meeting, and open a few URLs into a specific group — all from a script. That is what browser-cli is for.
It works by pairing a small browser extension with a Python package that provides both a CLI and SDK. The extension has full access to your browser's tabs, windows, groups, and page DOM. The CLI and SDK talk to it in real time over a local IPC channel.
How it works
terminal / python script
│
│ Local IPC (Unix socket on Linux/macOS, named pipe on Windows)
▼
Native Messaging Host (Python process, launched by the browser)
│
│ Native Messaging Protocol (stdin/stdout, 4-byte length prefix + JSON)
▼
Browser Extension (background worker/page)
│
│ extension APIs
▼
Your running browser
- The extension calls
chrome.runtime.connectNative('com.browsercli.host')on startup. - The browser launches the native host Python process (registered in the OS).
- The native host opens a local IPC endpoint for the CLI.
- CLI commands connect to that socket, send a JSON command, and wait for the result.
- The native host relays the command to the extension via stdout, receives the result via stdin, and sends it back to the CLI.
No server needs to be running beforehand. The browser manages the native host's lifecycle.
Message format
Every command is a JSON object:
{ "id": "uuid", "command": "tabs.list", "args": {} }
Every response:
{ "id": "uuid", "success": true, "data": [...] }
Installation
Requirements: Python 3.10+, uv, Chrome, Chromium, Brave, Edge, Vivaldi, or Firefox
Install with uv
Once published on PyPI, install the CLI as a uv tool:
uv tool install real-browser-cli
browser-cli --version
browser-cli install brave # or: chrome, chromium, edge, vivaldi, firefox
The PyPI package is named real-browser-cli; the installed command is still browser-cli.
For better remote-response compression, install the optional fast extra:
uv tool install "real-browser-cli[fast]"
To upgrade later:
uv tool upgrade real-browser-cli
Install from source
git clone <repo>
cd browser-cli
uv sync
uv run browser-cli install brave # or: chrome, chromium, edge, vivaldi, firefox
The install command will:
- Ask you to load the browser-specific extension package
- Show the stable extension ID used by that browser family
- Write the native messaging manifest to your OS so the browser can find the host
- Copy the native host into an internal
libexecdirectory and create a small wrapper outside yourPATH
After install, fully restart your browser (Quit and reopen — not just close the window). The extension will connect to the native host automatically on startup.
Only the browser-cli command needs to be on your PATH. The browser launches the native host wrapper directly from its absolute path in the native messaging manifest, and that wrapper imports the installed browser_cli.native.host entry point. On Windows the install command also registers the host in the current user's Registry for the selected browser.
Project structure
browser-cli/
├── browser_cli/
│ ├── __init__.py # Python SDK — BrowserCLI class and SDK entry point
│ ├── cli.py # Click CLI entry point
│ ├── client/ # Client-side command routing used by CLI and SDK
│ │ ├── core.py # send_command and remote command routing
│ │ ├── targets.py # Browser target discovery and socket resolution
│ │ ├── auth.py # Remote auth fields and key lookup
│ │ └── messages.py # Request/response helpers
│ ├── models.py # Tab and Group helper models
│ ├── native/ # Native messaging host internals
│ │ ├── host.py # Browser-launched native host entry point
│ │ ├── local_server.py # Local CLI IPC server
│ │ └── protocol.py # Chrome Native Messaging framing
│ ├── remote/ # Client-side remote browser support
│ │ ├── transport.py # TCP/TLS remote transport
│ │ └── registry.py # Saved remote endpoints/keys
│ └── commands/
│ ├── navigate.py # nav open/reload/back/forward/focus
│ ├── search.py # search engine shortcuts
│ ├── tabs.py # tab management
│ ├── groups.py # tab group management
│ ├── windows.py # window management
│ ├── dom.py # DOM querying and interaction
│ ├── extract.py # content extraction
│ └── session.py # session save/load
├── extension/
│ ├── manifest.json # MV3 extension manifest
│ ├── content.js # Content-script helpers
│ └── src/ # TypeScript source split by command area
│ ├── index.ts # Builds generated extension/background.js
│ └── content/ # Builds generated extension/content-dispatch.js
├── examples/
│ ├── demo.py # Python SDK walkthrough
│ └── demo.sh # Bash CLI walkthrough
├── tests/
│ ├── conftest.py # shared pytest fixtures
│ ├── test_api.py
│ ├── test_cli.py
│ ├── test_dom.py
│ ├── test_extract.py
│ ├── test_groups.py
│ ├── test_nav.py
│ ├── test_session.py
│ ├── test_tabs.py
│ └── test_windows.py
├── com.browsercli.host.json # native messaging manifest template
├── pyproject.toml # package metadata and CLI entry point
└── uv.lock # locked dependencies for uv
CLI reference
All commands are run with uv run browser-cli [--browser ALIAS] <command>.
If exactly one browser instance is connected, commands auto-target it. Use --browser ALIAS when multiple browser instances are connected. tabs list, tabs count, groups list, groups count, windows list, and session list aggregate across all active browsers when --browser is omitted; in that mode they show the source browser alias or UUID. You can inspect the active instances with browser-cli clients and assign a persistent profile alias from inside the target browser with browser-cli clients rename --browser <current-alias> <new-alias>. Closed browsers are removed from the client registry automatically.
Important: profile aliases are browser-instance aliases, not window aliases. Window aliases created with windows rename are only for targeting windows in commands like nav open --window work. If a browser instance has no explicit profile alias set, the native host gives it a generated UUID alias so multiple unaliased browsers stay distinct.
Navigation (nav)
# Open a URL (no focus stealing by default)
browser-cli nav open https://example.com
browser-cli nav open https://example.com --focus # bring opened tab/window forward
browser-cli nav open https://example.com --window work # into a named window
browser-cli nav open https://example.com --group research # into a tab group (name or ID)
# Reload
browser-cli nav reload # reload active tab
browser-cli nav reload 1234 # reload tab by ID
browser-cli nav hard-reload # bypass cache
# Navigate history
browser-cli nav back
browser-cli nav forward 1234 # forward in specific tab
# Jump to a tab by URL pattern
browser-cli nav focus github # focuses first tab whose URL contains "github"
Search
Each search command opens the search results in your browser using the same flags as nav open.
browser-cli search google openai api
browser-cli search brave rust iterators
browser-cli search ddg tab groups --window work
browser-cli search youtube browser automation
browser-cli search yt lo fi
browser-cli search spotify aphex twin
browser-cli search amazon mechanical keyboard
browser-cli search ecosia native messaging
browser-cli search furaffinity dragons
browser-cli search fa dragons
browser-cli search bing browser cli
browser-cli search github browser-cli
browser-cli search wikipedia native messaging
browser-cli search wiki native messaging
browser-cli search reddit chrome extensions
browser-cli search stackoverflow click choices
browser-cli search so click choices
Tabs
browser-cli tabs list # list all open tabs (all windows)
browser-cli tabs count # count all tabs
browser-cli tabs count youtube # count tabs matching URL pattern
browser-cli tabs filter youtube # list tabs matching URL pattern
browser-cli tabs query "pull request" # search tabs by URL or title
browser-cli tabs active 1234 # switch browser focus to tab
browser-cli tabs html # print full HTML of active tab
browser-cli tabs html 1234 # print HTML of specific tab
browser-cli tabs close 1234 # close specific tab
browser-cli tabs close --inactive # close all inactive tabs
browser-cli tabs close --duplicates # close duplicate URLs (keep first)
browser-cli tabs dedupe # same as close --duplicates
browser-cli tabs move 1234 --window 2 # move tab to another window
browser-cli tabs move 1234 --group 42 # move tab into a group
browser-cli tabs sort --by domain # sort tabs within each window
browser-cli tabs sort --by title
browser-cli tabs sort --by time
browser-cli tabs merge-windows # pull all tabs into the current window
Tab groups
browser-cli groups list # list all tab groups
browser-cli groups count # count groups
browser-cli groups query "work" # search groups by name
browser-cli groups tabs 42 # list tabs inside group ID 42
browser-cli groups create "research" # create a new group
browser-cli groups add-tab research # open a blank tab in the group
browser-cli groups add-tab research https://example.com # open URL in the group
browser-cli groups add-tab 42 https://example.com # by group ID
browser-cli groups close 42 # ungroup the group
browser-cli groups move research --forward # move group right
browser-cli groups move research --right # same as --forward
browser-cli groups move research -r # short right alias
browser-cli groups move 42 --backward # move group left
browser-cli groups move 42 --left # same as --backward
browser-cli groups move 42 -l # short left alias
Windows
browser-cli windows list # list all windows
browser-cli windows open # open a new window
browser-cli windows open https://example.com # open a new window on a URL
browser-cli windows rename 1 "work" # give a window a local alias
browser-cli windows close 1 # close a window
DOM
These commands run on the active tab. The tab must be on a regular http:// or https:// page — not a browser internal page like brave://newtab.
browser-cli dom query "h1" # return elements matching CSS selector
browser-cli dom text "h1" # get text content of matching elements
browser-cli dom attr "a" href # get attribute value from elements
browser-cli dom exists ".modal-banner" # exits 0 if found, 1 if not
browser-cli dom click ".accept-button" # click an element
browser-cli dom type "#search" "hello" # type text into an input
Extract
browser-cli extract links # all <a href> links on the page
browser-cli extract images # all <img> tags (src + alt)
browser-cli extract text # all visible text (innerText)
browser-cli extract json "#data" # parse JSON inside a CSS selector
browser-cli extract html # full HTML of the active tab
browser-cli extract markdown # main page content as Markdown
browser-cli extract markdown --selector "article" # specific DOM subtree as Markdown
Sessions
A session is a snapshot of all open tab URLs, stored inside the extension via chrome.storage.local. Sessions survive browser restarts but are lost if the extension is uninstalled or extension data is cleared.
browser-cli session save before-meeting # save current tabs as a named session
browser-cli session load before-meeting # reopen all saved tabs
browser-cli session list # list all saved sessions (name, tab count, date)
browser-cli session remove before-meeting # delete a saved session
browser-cli session diff session-a session-b # show which URLs were added / removed
browser-cli session auto-save on # auto-save after every tab change
browser-cli session auto-save off
Misc
browser-cli clients # show connected browser info from the registry
browser-cli clients rename --browser abcd1234 work # rename one connected browser instance
browser-cli --browser abcd1234 clients rename work # equivalent global form
browser-cli install brave # (re)register the native host
browser-cli completion zsh # print setup instructions
browser-cli completion zsh --script # output raw completion script
Python SDK
from browser_cli import AsyncBrowserCLI, BrowserCLI
b = BrowserCLI()
Commands are grouped into namespaces on the client (b.tabs, b.dom, b.session, ...). Each sync call blocks until the browser responds and returns the data directly as a Python object. For asyncio programs, AsyncBrowserCLI exposes the same namespaces as native awaitable methods over async Unix/TCP transport.
# Navigation ── b.nav
b.nav.open("https://example.com")
b.nav.open("https://example.com", background=True)
b.nav.open("https://example.com", window="work")
b.nav.reload()
b.nav.hard_reload()
b.nav.back()
b.nav.forward(tab_id=1234)
b.nav.focus("github")
b.nav.to(1234, "https://example.com") # navigate a specific tab in place
b.nav.search("google", "python asyncio")
# Tabs ── b.tabs
tabs = b.tabs.list() # list[Tab]; in multi-browser mode each tab.browser is set
tab = b.tabs.open("https://example.com") # returns a bound Tab object
tab = b.tabs.open("https://example.com", wait=True, timeout=10)
active = b.tabs.active() # active Tab object
tab = b.tabs.get(1234) # tab by ID
tab = b.tabs.first("github") # first matching tab or None
b.tabs.activate(1234)
b.tabs.close(1234)
b.tabs.close(tab_ids=[1, 2, 3]) # close many in one round-trip (IDs or Tab objects)
b.tabs.close_inactive()
b.tabs.close_duplicates()
b.tabs.filter("youtube") # list of matching tabs
b.tabs.query("pull request")
counts = b.tabs.count("github") # int, or BrowserCounts(total=..., by_browser=...) in multi-browser mode
html = b.tabs.html() # full HTML string of active tab
b.tabs.sort(by="domain")
b.tabs.merge_windows()
b.tabs.dedupe()
# Bound Tab helpers
tab = b.tabs.active()
tab.pin()
tab.screenshot()
tab.refresh()
tab.wait_for_load(timeout=10)
tab.watch_url(r"/done$")
# Tab groups ── b.groups
groups = b.groups.list() # list[Group]; in multi-browser mode each group.browser is set
b.groups.create("research") # creates group, returns Group
b.groups.close(42)
b.groups.tabs(42) # tabs inside a group
b.groups.add_tab(42, "https://example.com")
b.groups.count() # int, or BrowserCounts(...) in multi-browser mode
# Windows ── b.windows
windows = b.windows.list() # in multi-browser mode each dict has a "browser" key
b.windows.rename(1, "work")
b.windows.open()
b.windows.open("https://example.com")
b.windows.close(1)
# DOM ── b.dom (active tab must be http/https)
elements = b.dom.query("h2") # list of { tag, text, attrs }
texts = b.dom.text(".article p") # list of strings
attrs = b.dom.attr("a", "href") # list of strings
exists = b.dom.exists(".modal-banner") # bool
b.dom.click(".accept-button")
b.dom.type("#search", "hello world")
b.dom.wait_for("#results", visible=True, timeout=10)
b.dom.eval("document.title")
# Extract ── b.extract
links = b.extract.links() # list of { text, href }
images = b.extract.images() # list of { alt, src }
text = b.extract.text() # string
data = b.extract.json("#app-data") # parsed Python object
md = b.extract.markdown("article")
# Page / storage
info = b.page.info()
b.storage.set("token", "abc")
val = b.storage.get("token")
# Sessions ── b.session
b.session.save("before-meeting")
b.session.load("before-meeting")
sessions = b.session.list() # [{ name, tabs, savedAt }, ...]
b.session.remove("before-meeting")
diff = b.session.diff("session-a", "session-b")
# diff = { "added": [...urls], "removed": [...urls] }
b.session.auto_save(True)
# Performance + extension
b.perf.status()
b.perf.set_profile("gentle")
b.extension.reload()
# Workflow decorators ── b.decorators
@b.decorators.new_tab("https://example.com", wait=True, close=True)
def scrape(*, tab):
return b.extract.markdown("article")
@b.decorators.wait_for_selector("#ready", visible=True)
def run_after_page_ready():
return b.dom.text("#ready")
@b.decorators.performance_profile("ultra")
def restore_big_session():
return b.session.load("work", lazy=True)
@b.decorators.retry(times=3, delay=1)
@b.decorators.save_session_before("before-risky-step")
def risky_workflow():
b.tabs.close_duplicates()
# Async SDK: same namespaces, native awaitable methods
async def async_example():
ab = AsyncBrowserCLI()
tabs = await ab.tabs.list()
@ab.decorators.new_tab("https://example.com", wait=True, close=True)
async def scrape(*, tab):
return await ab.extract.markdown("article")
return tabs, await scrape()
# Misc
clients = b.clients()
raw = b.command("tabs.count", {"pattern": "github"}) # escape hatch for raw commands
Error handling
from browser_cli import BrowserCLI, BrowserNotConnected
b = BrowserCLI()
try:
tabs = b.tabs.list()
except BrowserNotConnected:
print("Browser is not running or extension is not loaded")
except RuntimeError as e:
print(f"Browser returned an error: {e}")
from browser_cli import BrowserCLI, BrowserCounts
b = BrowserCLI()
tabs = b.tabs.list()
for tab in tabs:
print(tab.browser, tab.title)
counts = b.tabs.count()
if isinstance(counts, BrowserCounts):
print(counts.total)
print(counts.by_browser)
Example scripts
See examples/demo.py (Python) and examples/demo.sh (Bash) for full walkthroughs covering tabs, groups, DOM extraction, and session management.
uv run python examples/demo.py
bash examples/demo.sh
Development
npm ci
npm run check:extension # type-check, build extension bundles, syntax-check bundle
uv run pytest -q
On NixOS or hosts without global Node/npm:
nix-shell # automatically runs npm ci when node_modules is missing/outdated
npm run check:extension
The extension source lives in extension/src/. extension/background.js and extension/content-dispatch.js are generated and ignored by git. Run npm run build:extension before using Load unpacked with extension/. On NixOS, use nix-shell first if npm is not installed globally.
Packaging:
npm run package:extension # testing/unpacked zip, keeps manifest.key for stable Chromium native-messaging ID
npm run package:extension:webstore # Chrome Web Store zip, strips manifest.key
npm run package:extension:firefox # Firefox zip, strips manifest.key and Firefox-incompatible permissions
Chrome Web Store rejects manifest.key, so upload the *-webstore-* zip from dist/. For Firefox, use the *-firefox-* zip.
Limitations
- Browser internal pages (
chrome://,brave://,edge://,about:) cannot be scripted. DOM and extract commands only work on regularhttp://andhttps://pages. - Multiple browser instances can be auto-distinguished, but generated aliases are temporary. Unaliased browsers get UUID aliases from the native host, which avoids collisions but is less ergonomic than setting a stable alias with
browser-cli clients rename --browser <current-alias> <new-alias>. - Supported install targets are explicit, not “all Chromium browsers”. The installer currently supports Chrome, Chromium, Brave, Edge, Vivaldi, and Firefox. Other Chromium-based browsers may use different or shared native messaging manifest locations, so they need browser-specific verification before being added safely.
- Firefox support is experimental. Basic tab/window/navigation/native-messaging support is wired, including tab-group APIs on supported Firefox versions.
License
PolyForm Noncommercial License 1.0.0. See LICENSE.
Commercial use is not permitted under this license. For commercial licensing, contact the project maintainer.