clearcote (Python SDK)

A Playwright drop-in for Clearcote — the open, reproducible, anti-fingerprint Chromium build. launch() returns a standard Playwright Browser, so migrating is a one-line import change.

The verified Clearcote binary is auto-downloaded and SHA-256 checked on first use, then cached — no zips or paths to manage.

Platform: Clearcote ships Windows x64 and Linux x64 binaries; launch() runs on both and the SDK auto-downloads the right one for your OS. On Linux the persona is Linux-native (Linux GPU/voices/audio-device values) and DRM uses the Linux CDM. macOS is on the roadmap. On a minimal Linux host, install the browser's runtime libs (e.g. apt-get install -y libnss3 libnspr4 libgbm1 libasound2 libatk1.0-0 libatk-bridge2.0-0 libcups2 libdrm2 libxkbcommon0 libxcomposite1 libxdamage1 libxrandr2 libxfixes3 libxext6 libpango-1.0-0 libcairo2 libx11-6 libxcb1 libexpat1 libdbus-1-3) and pass args=["--no-sandbox"] (or chown root:root chrome-sandbox && chmod 4755 chrome-sandbox) in containers.

Install

pip install clearcote

playwright is pulled in as a dependency. You do not need to run playwright install (Clearcote uses its own browser binary, not Playwright's bundled Chromium).

Usage

from clearcote import launch

browser = launch(
    fingerprint="user-7423",        # per-eTLD+1 seed: same seed => same identity, different => unlinkable
    platform="windows",
    timezone="America/New_York",
    headless=False,
)
page = browser.new_page()
page.goto("https://abrahamjuliot.github.io/creepjs/")
# ... standard Playwright (sync API) from here ...
browser.close()

Already using Playwright? Swap p.chromium.launch(...) for launch(...) from clearcote — the returned object is a normal Playwright Browser. (One shared Playwright driver is started lazily and stopped at interpreter exit.)

Async API (clearcote.async_api)

Inside an asyncio event loop, use the async API — it mirrors the sync one and returns Playwright async objects (the sync API raises "Sync API inside the asyncio loop"):

import asyncio
from clearcote.async_api import launch

async def main():
    browser = await launch(
        fingerprint="user-7423",
        platform="windows",
        timezone="America/New_York",
    )
    page = await browser.new_page()
    await page.goto("https://abrahamjuliot.github.io/creepjs/")
    # ... standard Playwright (async API) from here ...
    await browser.close()

asyncio.run(main())

Same options as the sync launch (fingerprint/persona/proxy/geoip/profile/canvas_bridge/ humanize/…). clearcote.async_api exposes launch, launch_persistent_context, launch_agent, run_agent_task, executable_path, download, plus Profile (use launch(profile="name")). Each launched browser owns its Playwright driver and stops it on await browser.close().

Light stealth (light_stealth=True)

When the full seed-derived persona is more than a target needs, light_stealth spoofs only a coherent, seed-derived bundle of the safe metadata axes — hardware_concurrency, device_memory, color_depth, device_pixel_ratio, max_touch_points — via native override switches, leaving rendering (canvas/WebGL/audio/fonts), TLS and the real browser version untouched. Screen dimensions stay real by default (opt-in), since a faked screen that can't be reconciled with the real render surface is a reliable block trigger. It never engages the --fingerprint persona machinery.

browser = launch(light_stealth=True, fingerprint="my-seed")   # coherent metadata, rendering left real

Or set any native override directly (no seed needed) — an explicit value always wins over the persona:

browser = launch(hardware_concurrency=8, device_memory=8, device_pixel_ratio=1.25, max_touch_points=0)

Native overrides: hardware_concurrency, device_memory, color_depth, device_pixel_ratio, max_touch_points, and (opt-in) screen_width / screen_height / avail_width / avail_height. Needs the Clearcote 149.0.7827.114 (v0.1.0-pre.22) build or newer.

Standing CDP endpoint (serve())

Run Clearcote as a stealthy CDP endpoint that any existing automation attaches to unchanged — Playwright's connect_over_cdp, puppeteer.connect, or browser-use / Crawl4AI / Stagehand. Where launch() spawns a Playwright-owned browser, serve() launches the binary directly — so --enable-automation is never added and navigator.webdriver stays false; the port binds to loopback (127.0.0.1) behind an origin allowlist.

from clearcote import serve

srv = serve(fingerprint="seed-123", platform="windows")   # same persona/proxy/geoip options as launch()
print(srv.cdp_url)                                        # http://127.0.0.1:<port>

from playwright.sync_api import sync_playwright
browser = sync_playwright().start().chromium.connect_over_cdp(srv.cdp_url)   # your code, unchanged
# ... or puppeteer.connect / browser-use / Crawl4AI / Stagehand, pointed at srv.cdp_url ...
srv.close()                                               # or: `with serve(...) as srv:`

Or from the shell:

clearcote-serve --port 9222 --fingerprint seed-123 --platform windows   # prints http://127.0.0.1:9222

The returned Server exposes .cdp_url, .ws_url(), and .close(), and works as a context manager.

Drive it from an AI agent (MCP). Point Claude Desktop / Cursor / Cline at the clearcote-mcp server (pip install clearcote-mcp or npx -y clearcote-mcp) — ~20 tools over one shared stealth browser, persona set via CLEARCOTE_* env.

Through a proxy (report the proxy's IP, not your host's)

browser = launch(
    fingerprint="user-7423",
    proxy={"server": "http://host:8080", "username": "u", "password": "p"},  # standard Playwright option
    timezone="America/New_York",
    webrtc_ip="203.0.113.10",       # make WebRTC report the proxy egress IP, not your host's
)

WebRTC won't leak your real IP. The engine fabricates the WebRTC server-reflexive (srflx) candidate at webrtc_ip and sends no real STUN from your host — so WebRTC reports the proxy IP and your real IP never leaks at the packet level. A plain candidate "relabel" doesn't stop the leak (the real STUN packet still goes out from your host); Clearcote sends none. Raw host candidates are suppressed, and the candidate set stays coherent (not empty/disabled).

Auto geo-match (geoip)

Set geoip=True and Clearcote resolves the proxy's exit IP (looked up through the proxy) and auto-fills any unset timezone, accept_language, location, and webrtc_ip so the whole identity — clock, language, geo, and WebRTC IP — matches the proxy's region:

browser = launch(
    fingerprint="user-7423",
    proxy={"server": "http://host:8080", "username": "u", "password": "p"},
    geoip=True,              # timezone, languages, location, AND WebRTC IP all auto-set to the proxy's geo
)

Anything you set explicitly wins over geoip. With no proxy it uses your direct connection's IP. The lookup needs an http(s) proxy — SOCKS proxies are skipped (set timezone/accept_language yourself).

Geo data comes from the offline geoip-all-in-one MaxMind database (downloaded + cached on first use; GPL-3.0 data, the same source Camoufox uses) — more accurate than a single online API — with ip-api.com as a fallback.

Humanized input (humanize, show_cursor)

browser = launch(fingerprint="user-7423", humanize=True)
page = browser.new_page()
page.goto("https://example.com")

page.click("#login")                       # eased bezier glide, then a trusted click
page.fill("#user", "alice")                # focus + key-by-key typing with human timing
page.locator("#pwd").type("s3cr3t")        # locators are humanized too
page.mouse.wheel(0, 800)                   # eased, multi-step scroll
# a held-button drag (slider captchas): the button stays pressed across the move
page.mouse.move(x0, y0); page.mouse.down(); page.mouse.move(x1, y0); page.mouse.up()

humanize=True installs one consistent human-input standard covering moving, clicking, dragging, scrolling and typing — all dispatched as native trusted input (isTrusted === true, navigator.webdriver stays false), at both the page level (page.click/hover/dblclick/ type/fill/press, page.mouse.*, page.keyboard.type) and the locator level (locator.click/type/fill/hover/press_sequentially/drag_to/check/…). Mouse paths are slightly bowed cubic-beziers built from the last cursor position (no snap back to the corner), walked as a sum of sub-movements with a min-jerk velocity profile — a ballistic primary that slightly over/undershoots plus a corrective move, i.e. the multi-peak velocity of real reaching, not one symmetric bell. Because they use native input, the button held by mouse.down() stays held across the move, so down → move → up is a real drag (slider captchas work). Clicks get an actionability pre-flight (visible + enabled + stable + not covered) and fall back to the native click if it fails. Typing goes key-by-key with gaussian inter-key timing + word-boundary pauses and the occasional fat-finger correction; page.fill over 200 chars stays atomic (skips per-key typing) to avoid crawling. Scrolling uses ease-out inertia (a fast flick decaying to a slow settle) with the occasional reading pause.

show_cursor=True injects a red cursor dot that follows the real mouse, handy for watching a headed run. Both default to off; everything stays standard Playwright when humanize=False.

Render-backend coherence check (check_render_coherence)

A persona can claim a GPU, but if the page is actually painted by a software rasterizer (SwiftShader/llvmpipe — common headless with no GPU) a strict detector can tell. Probe a live page:

from clearcote import launch, check_render_coherence

br = launch(fingerprint="user-7423")
page = br.new_page(); page.goto("about:blank")
verdict = check_render_coherence(page)        # {'renderer', 'software_suspected', 'coherent', 'warnings', ...}
if not verdict["coherent"]:
    print(verdict["warnings"])                 # e.g. software rasterizer / incoherent GPU family

It reads the (unmasked) WebGL vendor/renderer the page actually sees, flags a software rasterizer (a fatal headless tell — enable the canvas bridge or run headed on a real GPU) and an incoherent vendor/renderer pair. Pass claimed_gpu=... to also assert the rendered family. The async API exposes the same as await clearcote.async_api.check_render_coherence(page).

Hardened launch defaults

Every launch() already does, with no extra options:

• drops Playwright's --enable-automation so the engine's AutomationControlled feature stays off (it otherwise flips navigator.webdriver-adjacent tells). Pass your own ignore_default_args to override.
• disables QUIC/HTTP-3 when a proxy is set, so no UDP egresses around the proxy (a SOCKS5/HTTP proxy carries only TCP) — coherent with proxied Chrome.
• prints a one-line coherence warning to stderr for incoherent option combos it can't auto-fix (silence with quiet=True or CLEARCOTE_NO_WARN=1).

Persistent profile

from clearcote import launch_persistent_context

context = launch_persistent_context(
    "./profile-7423",
    fingerprint="user-7423",
    platform="windows",
)

Widevine / DRM (widevine=True)

clearcote ships the EME/Widevine plumbing compiled in, but — being 100% open source — it does not bundle Google's proprietary CDM. Pass widevine=True on a persistent context and the SDK fetches that CDM once from Google's own component server (same as a real Chrome receives it), seeds it into the profile, and enables it — so navigator.requestMediaKeySystemAccess('com.widevine.alpha') resolves and DRM streams play, instead of EME being a "no-Widevine" tell.

from clearcote import launch_persistent_context

ctx = launch_persistent_context("./profile-drm", widevine=True)   # fetch + seed + enable the CDM
page = ctx.pages[0] if ctx.pages else ctx.new_page()
page.goto("https://example.com")
ok = page.evaluate("""async () => {
  const a = await navigator.requestMediaKeySystemAccess('com.widevine.alpha',
    [{initDataTypes:['cenc'], videoCapabilities:[{contentType:'video/mp4;codecs="avc1.42E01E"',
      robustness:'SW_SECURE_DECODE'}]}]);
  await a.createMediaKeys(); return true;
}""")
print("Widevine:", ok)            # True
ctx.close()

• Requires a persistent context (the CDM lives in user_data_dir) — not the incognito launch().
• The CDM is cached under ~/.clearcote/WidevineCdm; fetch it ahead of time with fetch_widevine().
• It's opt-in: the clearcote package never distributes Google's CDM — you trigger the download.
• Software-secure (L3) playback. Hardware-secure (L1) paths are out of scope.

AI agent (OpenRouter)

Drive a page with an in-browser AI agent — it perceives the live page, asks an LLM what to do, and executes the steps as real, trusted input through Chrome's Actor framework. Defaults to OpenRouter; switch models with a single slug.

from clearcote import launch_agent, run_agent_task

ctx = launch_agent(
    agent_llm_key=OPENROUTER_API_KEY,        # turns the agent on
    agent_model="openai/gpt-4o-mini",        # any provider/model slug
)
page = ctx.pages[0] if ctx.pages else ctx.new_page()
page.goto("https://example.com")

result = run_agent_task(page, "Click the 'More information...' link.", max_steps=8)
print(result["success"], result["finalText"], result["steps"])
ctx.close()

• agent_llm_key is all you need — the engine auto-enables Chrome's Actor framework (no extra flags).
• agent_llm_url points at any OpenAI-compatible endpoint (default OpenRouter); agent_tool_mode is "tools" (function-calling) or "json".
• Override the model per task: run_agent_task(page, goal, model="anthropic/claude-3.5-sonnet").
• The agent needs a regular profile — use launch_agent / launch_persistent_context, not the incognito launch().

Capture or import a profile

Instead of the synthetic seed-derived identity, you can have Clearcote present a real machine's fingerprint. Pass it to launch() via fingerprint_profile — fields present in the profile override the seed-derived persona; absent fields fall back to the fingerprint seed, so partial profiles stay coherent.

1. Capture from a donor Chrome — open tools/fingerprint-collect/collect.html and click Capture (downloads a JSON), or paste the collector script in DevTools. It records an exhaustive profile (navigator, screen, WebGL, audio, speech voices, fonts, codecs, CSS media, WebGPU, WebRTC). See the collector README.

2. Or convert from the open-source 10k dataset — chrome-fingerprints:

pip install chrome-fingerprints
python tools/fingerprint-collect/convert_dataset.py --out ./profiles --count 100

3. Launch with the profile:

browser = launch(
    fingerprint="seed-1",                 # seeds any field the profile doesn't specify
    fingerprint_profile="profile.json",   # path / dict / JSON string — SDK gzip+base64-encodes it
)

Fingerprint options

All optional. Anything not listed here is passed straight through to Playwright (headless, proxy, args, timeout, slow_mo, …).

Headed launches default to no_viewport=True so window.innerWidth tracks the real OS window — an emulated 1280×720 on a real window is an impossible-window tell. Pass an explicit viewport to override.

Headless launches (0.24.0+) get a coherent window geometry by default, so screen, availWidth/Height, innerWidth/Height and outerWidth/Height agree with each other the way a real window's do. With a fingerprint seed the engine's own screen and work area are used and the window is sized to them; without a seed the SDK applies a screen size drawn from real captured desktops and fits the viewport to it. It is applied at launch, before your first navigation. Pass an explicit viewport, screen or no_viewport to opt out entirely.

Proxies: a socks5://user:pass@host:port proxy is routed via --proxy-server (Playwright rejects credentials in its SOCKS descriptor). Chromium can't authenticate SOCKS5, so the credentials are dropped with a warning — put the auth on a local relay.

Personas & Client Hints coherence

A persona's Client Hints are coherent across JavaScript and HTTP by construction — clearcote rewrites a single blink::UserAgentMetadata (brand list, full-version list, platform, mobile, arch/bitness) that feeds both the browser path that attaches the Sec-CH-UA* request headers and the renderer path that builds navigator.userAgentData. There aren't two sides to keep in sync; they read the same source. So getHighEntropyValues(['fullVersionList', …]) in JS matches Sec-CH-UA-Full-Version-List on the wire, userAgentData.platform matches Sec-CH-UA-Platform, and so on.

Chrome — the default and the recommendation (most coherent: clearcote is Chromium, so the claim matches the engine's real behavior):

browser = launch(fingerprint="p1")   # brand defaults to Chrome; platform defaults to the host OS
# HTTP:  sec-ch-ua: "Google Chrome";v="149", "Chromium";v="149", "Not)A;Brand";v="…"
#        sec-ch-ua-mobile: ?0    sec-ch-ua-platform: "Windows"
# JS:    navigator.userAgentData.brands == that same list; mobile=False; platform="Windows"

Edge — a coherent Edge string surface (UA + UA-CH), for targets that specifically expect the Edge brand:

browser = launch(fingerprint="p1", brand="Edge")
# UA:    …Chrome/149.0.0.0 Safari/537.36 Edg/149.0.0.0
# HTTP:  sec-ch-ua: "Microsoft Edge";v="149", "Chromium";v="149", "Not)A;Brand";v="…"
#        sec-ch-ua-full-version-list: "Microsoft Edge";v="149.0.3650.65", "Chromium";v="149.0.7827.114", …
# JS:    userAgentData.brands include "Microsoft Edge"; getHighEntropyValues(['fullVersionList'])
#        carries that same distinct Edge build — JS and HTTP identical, from one metadata.

brand ("Chrome" | "Edge" | "Opera" | "Vivaldi") is a string-level persona: it changes the UA + UA-CH brand, but the engine still behaves like Chromium. Chrome is the most coherent default (nothing to contradict); reach for brand="Edge" only when a target expects it. If you also set brand_version to an older major, the network tls_profile (default match-persona) shifts the TLS shape to that major while the JS engine stays at the build version — so Chrome ≈ the build version, everything aligned is the strongest persona.

Android — a best-effort mobile persona (seed-selected Pixel/Galaxy):

browser = launch(fingerprint="p1", platform="android")   # auto-sets a phone --window-size
# UA:    …(Linux; Android 10; K) … Chrome/149.0.0.0 Mobile Safari/537.36
# JS/HTTP: sec-ch-ua-mobile: ?1, platform="Android", model + platformVersion; maxTouchPoints=5,
#          pointer:coarse / hover:none, mobile screen + DPR, Mali/Adreno WebGL, plugins=0.

Android is best-effort on a desktop engine: the JS/header surface is coherent, but the GPU render and fine page geometry (innerWidth floors at ~500px) stay desktop — documented residual tells. Pair with canvas_bridge for render coherence.

Saved profiles (Profile)

A Profile bundles a persona (seed, GPU, brand, …) and its canvas_bridge config under one name you can persist and re-launch — the claimed GPU, the bridge endpoint, and the bridge's GPU-keyed cache stay coherent because they travel together.

from clearcote import Profile, launch

# save once
Profile("acct-1", {
    "fingerprint": "acct-1",
    "gpu_vendor": "Google Inc. (Intel)",
    "gpu_renderer": "ANGLE (Intel, Intel(R) UHD Graphics ... D3D11)",
    "canvas_bridge": {"url": "ws://127.0.0.1:9099", "auth": "user:secret"},
}).save()

# re-launch anywhere (explicit kwargs override the saved options)
browser = Profile.load("acct-1").launch(headless=False)
# equivalently: launch(profile="acct-1")

Profiles are JSON at ~/.clearcote/profiles/<name>.json (set CLEARCOTE_PROFILE_DIR to relocate).

API

• launch(**options) → Playwright Browser. Pass profile= (a name, path, or Profile) to launch a saved persona.
• launch_persistent_context(user_data_dir, **options) → Playwright BrowserContext.
• serve(**options) → Server — a standing, stealthy CDP endpoint (.cdp_url / .ws_url() / .close(); context manager) any Playwright/Puppeteer/CDP client attaches to. Also exposed as the clearcote-serve CLI.
• executable_path(executable_path=None, cache_dir=None, quiet=False) → str — resolve (download/verify if needed) the chrome.exe path.
• download(cache_dir=None, quiet=False) → str — pre-fetch + verify without launching.
• Profile — Profile(name, options), .save(path=None), Profile.load(name), .launch(**overrides), .launch_persistent_context(dir, **overrides); plus list_profiles(), load_profile(name).
• RELEASE — the pinned release metadata (tag, version, sha256).

Binary resolution & verification

launch() resolves the browser in this order:

1. executable_path= argument, if given;
2. CLEARCOTE_BINARY environment variable, if set;
3. otherwise download the pinned release, verify its SHA-256 (the hash is baked into this package — it's the trust anchor), extract to a per-version cache, and verify the extracted chrome.exe hash too.

Cache location (override with CLEARCOTE_CACHE):

• Windows: %LOCALAPPDATA%\clearcote\Cache\<tag>
• macOS: ~/Library/Caches/clearcote/<tag>
• Linux: ${XDG_CACHE_HOME:-~/.cache}/clearcote/<tag>

A SHA-256 mismatch is a hard error — the SDK refuses to run an unverified binary. You can independently confirm the published checksums and GPG signatures on the release page.

Stay on the latest build (auto_update)

By default the SDK installs the exact browser build pinned into this package — reproducible, and the baked-in SHA-256 is the trust anchor. To follow new browser releases without upgrading the package every time, opt in:

browser = launch(fingerprint="seed-123", auto_update=True)

or set the environment variable globally:

CLEARCOTE_AUTO_UPDATE=1

With auto_update, the SDK resolves the newest GitHub release, downloads its zip, and verifies it against that release's published SHA256SUMS.txt. When a gpg binary is available it additionally imports the release's public key, confirms its fingerprint equals the pinned CA96F185 F96A693A EDB3AC1F CB00D851 B7A86B0F, and verifies the signed checksum — so an auto-resolved build is cryptographically authenticated, not just downloaded. If GitHub is unreachable it falls back to the pinned release; if the latest release is the pinned one, the audited baked-in hashes are used. Each build is cached per tag, so this only downloads when a new version actually ships. (For locked-down/reproducible deployments, leave auto_update off and bump the package deliberately.)

Choosing a browser version

By default the SDK downloads the exact build pinned into this package. To pick a specific browser major/version instead, pass version= (or set CLEARCOTE_BROWSER_VERSION):

launch(fingerprint="seed-1", version="149")      # newest 149.x (free)
launch(version="149.0.7827.114")                 # an exact build
launch(version="latest")                         # newest you can access
launch(version="150", license_key="cc_lic_...")  # a PRO-tier version (see below)

The request is resolved against a public catalog (GET /api/v1/versions) and validated to exist before anything downloads, so a bad request fails fast instead of getting stuck:

• unknown version → No Clearcote build matches version '151'. Available: 149.0.7827.114 (free).
• a PRO-tier version without a key → Clearcote 150… is a PRO build … set a license key (CLEARCOTE_LICENSE_KEY).

Free versions download from GitHub (no key needed); PRO versions download via the authenticated route. Each build is cached per version, so different majors coexist. Binary resolution order: executable_path > CLEARCOTE_BINARY > version > pinned default. Works the same in the async API, executable_path(), and download().

PRO tier (license key)

Everything above is the free build. A PRO license adds floating-concurrency licensing and pulls a separate, license-gated browser build. It's opt-in and entirely additive — with no license key the SDK is byte-for-byte the free client (free binary from GitHub, and it never contacts the license backend).

What's in each tier

The identity surface is free in full. PRO does not unlock "more spoofing" — every fingerprint control below is in the free build. What PRO adds is behavioural realism that needs recorded data or engine work held out of the public tree, plus the licensing itself.

The mouse tier is decided at runtime from a signed claim in the run-token — same SDK call, same humanize=True. With a valid PRO lease the motion comes from recorded human trajectories; without one it falls back to the synthetic bézier path. Nothing in your code changes.

Pass a license_key (or set CLEARCOTE_LICENSE_KEY, or drop it in ~/.clearcote/license.key):

browser = launch(fingerprint="seed-123", license_key="cc_lic_...")

When a key is present the SDK:

1. downloads the PRO binary via the site's authenticated GET /api/v1/download/pro route (short-lived signed URL), verified against its SHA-256 exactly like the free pin, then cached;
2. checks out one concurrency slot — a background heartbeat keeps it alive and rotates a short-lived run-token, and the slot is released when the browser closes.

The PRO engine refuses to launch without a valid run-token, so a copied binary alone won't run. Resolution order for the binary is executable_path → CLEARCOTE_BINARY → PRO (licensed) → free — an explicit binary always wins. A revoked/expired key raises (ConcurrencyLimitError / LicenseRevokedError / LicenseError); it never silently downgrades to the free binary. Override the backend with license_api_base or CLEARCOTE_LICENSE_API. Works the same in the async API.

License

BSD-3-Clause. See LICENSE.