Moving your automation code between two vendors: what actually breaks
Why you end up doing this at all
Nobody sets out to rewrite their automation stack. It usually happens because pricing changed, a profile format got deprecated, support went quiet, or a tool you were relying on for a specific fingerprint trait quietly dropped it. Whatever the trigger, once you’ve built real automation on top of an anti-detect browser’s local API, moving to a different vendor is not a copy-paste job. The browsers all do roughly the same job: they launch a Chromium or Firefox instance with a modified fingerprint profile and expose that instance to your scripts through a local REST API or a WebDriver-compatible endpoint. But the details of how each one does it differ enough that your existing code will break in specific, predictable places.
This is written from the operator side, not the vendor side. I run proxy infrastructure and test these tools against real detection systems, and I’ve moved automation between a few of them over time. None of what follows is a claim that switching tools makes your accounts safer. It doesn’t. It just changes which API you’re calling.
The part that stays the same
Most anti-detect browsers converge on a similar architecture: a local daemon (Multilogin’s Local API, GoLogin’s local server, Kameleo’s local API, AdsPower’s local API, Dolphin Anty’s local API) that you talk to over HTTP, usually on localhost with a fixed port. You send a request to start a profile, get back a debugging endpoint (usually a webSocketDebuggerUrl or a driver/port pair), and then drive that browser instance with Selenium, Playwright, or Puppeteer exactly as you would any local Chrome install.
That shared shape is why migrations feel deceptively easy at first. The Selenium or Playwright code that clicks buttons, fills forms, and reads page content barely needs to change, because it’s talking to a standard CDP or WebDriver connection, not to the vendor’s proprietary layer. What changes is everything before that: authentication, profile creation, profile launch, and how you read back the automation endpoint.
Where the breakage actually happens
Authentication and session handling. Some tools authenticate the local API with a token you generate in account settings and pass as a header on every call. Others expect you to be logged into the desktop app first, with the local API only usable while that app session is active. If your old code assumed a standalone token and the new vendor ties the API to an active app login, your scripts will fail with an auth error that has nothing to do with your actual automation logic.
Profile creation payloads. This is where the real rewrite happens. Each vendor structures its profile object differently: how proxy credentials are nested, whether WebRTC handling is a top-level field or buried under a fingerprint sub-object, how canvas and WebGL noise settings are named, whether screen resolution and timezone are auto-derived from the proxy or need to be set explicitly. If you were generating profiles programmatically (which most people doing this at any scale are), you’re rewriting your profile schema, not just swapping an endpoint URL. I’ve seen migrations stall for days purely because a field like os expected "win" in one tool and "windows" in another, and the API returned a generic 400 instead of telling you which field was wrong.
Launch response format. After you request a profile launch, you need the connection info to hand to Selenium or Playwright. Some vendors return a raw CDP WebSocket URL you plug straight into Puppeteer’s connect(). Others return a WebDriver-style port you build a Remote driver against. A few wrap the response in extra metadata you have to parse out first. If your code assumes one shape and gets the other, it won’t error clearly, it’ll just hand your automation framework a malformed endpoint and fail downstream in a way that looks like a browser crash.
Proxy assignment. Whether proxy config lives on the profile object or gets passed at launch time varies, and so does the list of supported proxy types (HTTP, SOCKS5, sometimes vendor-specific formats for mobile or residential rotation). If you’re managing your own proxy pool and rotating IPs per profile, this is the field you’ll be debugging most, because a malformed proxy string is often the difference between a profile that launches clean and one that launches with no outbound connection at all.
Rate limits and concurrency ceilings. The local APIs aren’t infinite. Vendors cap how many profiles you can launch concurrently, and that cap is rarely documented in the API reference, it shows up as a stall or an error under load. If your old tool tolerated 30 concurrent launches and the new one chokes at 15, your batch scripts need throttling logic they didn’t have before.
Fingerprint parity is not guaranteed
This is the part people skip and shouldn’t. Anti-detect browsers don’t all implement the same fingerprint traits, and even when they claim to cover the same categories (canvas, WebGL, audio context, fonts, screen, hardware concurrency, timezone-to-IP consistency), the depth of that spoofing differs. One tool might handle canvas noise well but leave WebGL renderer strings inconsistent with the reported GPU. Another might nail hardware fields but not touch AudioContext fingerprinting at all. Detection systems like those used by major ad platforms and marketplaces check for internal consistency across all of these signals, not just whether any single one looks fake.
What this means practically: moving your automation code to a new vendor is not just an API migration, it’s a fresh round of fingerprint testing. Run the new tool’s profiles through a fingerprint checker (browserleaks, or your own comparison against a real device) before you trust it with live accounts. Don’t assume that because vendor A’s spoofing held up for your use case, vendor B’s will too, even if the API calls map cleanly. I’ve tested tools that were rock solid on canvas and audio consistency but generated screen resolution and timezone combinations that didn’t match the GPS-plausible location their proxy was assigned to, which is exactly the kind of mismatch automated detection is built to catch. None of this means any given tool is unbannable or safe by default. It means the only way to know where a tool actually stands is to test it against the same checks a real platform would run, not to take a migration guide’s word for it.
A practical order of operations
If you’re doing this migration for real, the sequence that causes the fewest surprises:
- Map your old profile-creation payload field by field against the new vendor’s API docs before writing any code. Don’t guess field names from memory of the old tool.
- Build a single test profile manually through the new vendor’s UI first, so you know what a correctly configured profile object looks like from their side, then reverse-engineer your payload from that.
- Get one profile launching and connecting via Selenium/Playwright before touching your batch or scheduling logic. Concurrency bugs are much harder to debug once they’re mixed in with fingerprint bugs.
- Run fingerprint checks on the new profiles independently of your automation, before you route real accounts through them.
- Only then port over your rotation, proxy assignment, and scheduling code, and add throttling if the new vendor’s concurrency ceiling is lower than what you’re used to.
None of this is exotic engineering. It’s mostly patience and reading the actual API response bodies instead of assuming they match what you had before. The tools that make this easiest are the ones with clear, versioned API documentation and predictable error messages when a field is wrong, which is itself worth weighing alongside price and fingerprint quality when you’re choosing where to land.
If you’re deciding between vendors and want to see how their APIs and fingerprint output actually compare side by side rather than take a marketing page’s word for it, that’s what we test on the channel and write up here.
Get new guides and videos first — join the Telegram channel.