sleight

Drive any CDP browser like a human. Bezier trajectories with real hand tremor, typing rhythm modelled on keystroke-dynamics research, and exclusive leasing for browser instance pools.

Python ≥ 3.11 · one runtime dependency (websocket-client) · MIT

📖 中文文档手册 — 安装、快速开始、实战场景、CloakBrowser Manager 部署 🚀 部署与运维 CLI — 一条命令把 Manager 部署到本机或远程

pip install sleight

30 seconds

from sleight import connect, Text

with connect("http://127.0.0.1:9222") as s:      # opens its own tab, closes it on exit
    s.open("https://example.com", wait=Text("Example Domain"))
    print(s.title(), len(s.content()))

With a browser pool that has real profiles behind it:

from sleight.providers import CloakBrowserManager

mgr = CloakBrowserManager("http://127.0.0.1:19000", token="…")

with mgr.lease() as inst:                    # exclusive lease, released on exit
    with inst.session(human=True) as s:      # every action gets a human trajectory
        s.open("https://example.com")
        s.click("#login")
        s.type("#email", "user@example.com")
        s.click("#submit", human=False)      # …except this one, speed matters here

See what the page actually loaded — the library gives you structured data, you decide what to print:

with s.capture_resources(types={"Script", "Stylesheet"}) as capture:
    s.open(url, wait=Load())
    s.pump_events(10)          # the async batch that arrives after `load`

for r in capture.snapshot():
    print(r.resource_type, r.status, r.url)

Target one specific profile — by id, by name, or by tag. A name that matches nothing fails immediately with the visible names listed, rather than blocking until timeout:

with mgr.lease(instance_id="5edcc28a-…") as inst:              ...
with mgr.lease(name="Win-US-02") as inst:                      ...
with mgr.lease(where=lambda i: "us" in i.tags) as inst:        ...

handles = pool.lease_many(4, names=NAMES, timeout=60)   # rolls back on partial failure

Drag a slider — the buttons mask stays down for the whole haul, the trajectory overshoots and comes back, and there is a pause before the release, because releasing the instant you arrive is the most reliable machine tell there is:

s.drag("#captcha-knob", by=(212, 0), human=CAREFUL)
s.drag_and_drop("#card", "#done-column")     # HTML5 native drag, or a JS one — both

Rotate the exit IP. The tunnel hands out addresses per TCP connection and Chrome reuses keep-alive sockets, so a whole run pins to one IP. A fresh browser context is the only thing that reliably breaks that — clearing cache, unique query strings, and emulateNetworkConditions all do nothing (why):

with inst.context() as ctx, ctx.session() as s:   # own socket pool → new exit
    print(ctx.exit_ip())
    s.open(url)

Stop paying for bytes you throw away, and shed the tracking cookie afterwards:

with s.block(types=["Image", "Media", "Font"]) as blocked:
    s.open(url)
print(blocked.by_type)                       # {'Image': 34, 'Font': 6}

report = s.clear_site_data("https://example.com")
print(report.cookies)                        # ('datadome',) — what actually went away

Three providers' worth of instances, one logical pool:

from sleight import Pool
from sleight.providers import CloakBrowserManager, Plain

pool = Pool([
    CloakBrowserManager("http://10.0.0.1:9000", token=T1, name="hk"),
    CloakBrowserManager("http://10.0.0.2:9000", token=T2, name="sg"),
    Plain("http://127.0.0.1:9222", name="local"),
])

with pool.lease(where=lambda i: "us" in i.tags) as inst:
    ...

Getting a fleet to drive

The hard part of running CloakBrowser is not the driving — it is the deployment, the extension rollout, and the "why does this profile behave differently" archaeology. So the same package ships a CLI for it. Local docker or a remote host over SSH is the same code path, only the runner differs:

sleight hosts add hk-01 --ssh deploy@10.0.0.12 --dir /srv/cloakbrowser-manager --sudo
sleight deploy --host hk-01
sleight deployments add hk-01 second --dir /srv/cbm-2 --port 9001   # same box, second manager
sleight ext push ./plugins/bypass-paywalls --host hk-01   # MV3 check + permissions
sleight ext apply --host hk-01                            # every profile, then restart
sleight ext verify --host hk-01                           # did the browser really load it
sleight ui                                                # the same, in a browser

Hosts, the managers on each of them, and a deploy/backup/upgrade audit trail live in a local SQLite database (~/.sleight/sleight.db) that the CLI and the web UI share.

sleight ui walks you through it: connect a host (with a real connection test before anything is saved), pick a sizing template, preflight, deploy. Every option carries a one-line explanation of what breaks if you get it wrong plus a recommended value — defined once on the backend, rendered by both the CLI (sleight templates) and the UI.

Deploys are idempotent, --dry-run prints the exact bytes it would write, and the things you must not do are refused rather than documented: no latest tag, no down -v, no silently rotating an in-use AUTH_TOKEN, no second manager on the same /data. The engine is stdlib-only (SSH is the system ssh binary); only sleight ui needs pip install "sleight[ui]".

Why this exists

Fingerprint-level anti-detection is a solved problem — CloakBrowser patches Chromium at the source level, Camoufox patches Firefox. They fix what the browser looks like. Nothing fixes how it moves.

• Playwright and Puppeteer teleport the mouse. mouse.move(steps=N) interpolates a straight line at constant speed — zero jitter, zero acceleration. That is itself a signature.
• The browser will not fill in the trajectory for you. Even with a humanize feature enabled browser-side, an external CDP client produces zero mousemove events between press and release. Measured, not assumed.
• The good trajectory work lives in JavaScript (ghost-cursor). Python ports are thinly maintained.
• Crawlee for Python's BrowserPool does not support remote browsers.

sleight fills exactly that gap: Python + remote CDP + human behaviour + instance leasing.

Relationship to Playwright

Not a replacement — a complement. sleight is a driver layer, not a framework. It deliberately does not do iframes/OOPIF, downloads, video, tracing, or a full locator DSL. When you need those, use Playwright.

The interesting part is that you can use both: sleight's human module is sans-io — it emits (method, params, sleep_after) tuples and never touches a socket — so it drives a Playwright CDPSession just as happily as sleight's own transport.

What makes the motion credible

Parameters are not invented. They come from the WindMouse physical model, ghost-cursor's Fitts-law point budgeting, and published keystroke-dynamics measurements (alternating-hand digraphs average 114 ms, same-hand-different-finger 131 ms, same-finger slowest and most variable).

Scope

Does: navigation, reload and history · typed wait conditions · rendered-DOM reads · CSS queries · human mouse / keyboard / wheel / drag · element screenshots · forms (select_option, upload_file) · isolated browser contexts for exit-IP rotation · origin-scoped site-data clearing · request blocking via the Fetch domain · exit_ip() · structured network-resource capture · instance discovery across providers · cooperative exclusive leasing with TTL renewal (in-memory, or Redis-backed across processes) · idempotent recovery · deploying and operating CloakBrowser Manager over local docker or SSH, extensions included.

Does not: data extraction · scheduling and queues · fingerprint spoofing (that is the browser's job) · iframe / OOPIF / Shadow DOM piercing · strict fencing · WebDriver BiDi · Firefox.

The deploy layer lives in its own subpackage and is never imported by import sleight, so the driver stays a one-dependency library.

Known limits

Measured, not assumed. Each of these cost someone a day to find out:

Roadmap

Ordered by what actually blocks work, not by size.

• iframe / frame support — s.frames(), with s.frame(sel) as fs:. The one real gap. CAPTCHAs live in iframes (DataDome's does), so drag and element screenshots — both shipped — still cannot reach a slider inside one. Needs a frame tree, cross-frame coordinate mapping, and a separate session per OOPIF.
• Context vs. lightweight-instance resource numbers — memory, CPU, and time-to-ready for instance with proxy+plugin / bare instance / N contexts in one instance. Nobody should redesign their concurrency around contexts without this table, so the API stays an opt-in dimension until the numbers exist.
• launch_args_effective — get_profile() returns the configured launch args; the effective command line lives on the Manager side. Diagnosing proxy problems currently means reading chrome://version.

Status

0.x — alpha, the API will move. Every release documents its breaking changes in its git tag. Releases are published from that tag by .github/workflows/publish.yml via PyPI Trusted Publishing — no token is stored in this repository.

License

MIT