Twin Browser
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Runs while you’re away. Asks when it matters.

Your agent in the cloud. Inside your guardrails.

It works for you. Hand it a task and it gets it done in its own real browser, with your details and the accounts you connect. It keeps going after you close the tab, browses like a person, and asks you before anything you would want to decide.

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Try the console
  • Sign in with Google
  • Free to start, no card required
  • Secrets redacted from every log

Illustrative run; the site and steps are an example. Real runs start from the console below.

What Twin is

Works the way you would

Not a script you babysit, and not a chat that only answers. An agent with its own browser that does the task the way you would, and checks with you when it should.

Lives in the cloud

It works on our servers in its own real browser. Close the tab and the task keeps going; come back and you are watching it live. Monitors re-check a page on a schedule and report only when it changed.

Acts as you

It fills forms with the details you have told it, signs in with the accounts you connect, and types passwords from your vault at the last moment. The AI never sees them.

Inside your guardrails

It stops before Pay, Delete, Send or a password change and waits for your yes. It paces every account so it never floods a site, and it logs each step it takes.

Asks when it should

A 2FA code, an approval, a detail it does not have: the run pauses, asks you, and carries on from the same step. Codes from an inbox or phone you connect fill themselves.

Example steps and headline numbers, not live traffic.

Example steps and headline numbers, not live traffic.

Human, to the site

Browses like a person

Bot checks look for the tells of automation. Twin removes them at the source, so the sites you are allowed to use do not turn your agent away.

  • Moves and types like a hand

    Wherever a site can score it — signing in, filling a form, submitting, any page carrying a bot sensor — curved pointer paths with the odd overshoot and key-by-key typing at a human pace. Plain browsing elsewhere runs at full speed.

  • One identity that adds up

    A residential exit in the country you pick, with the browser’s language and timezone set to match. A returning profile keeps its cookies between runs.

  • Real Chrome when a site pushes back

    The run steps up to the stealth browser: real, windowed Chrome with no webdriver flag, no automation-protocol leak and no WebRTC address leak. On Pro.

  • Knows which wall it hit

    A blocked run names the bot check behind it. A challenge is retried on stealth; a reputation wall comes to you once as a sign-in, and later runs reuse it.

How the stealth browser works

The Twin Browser API

One engine, two ways in. Send a goal and the target you authorize; get the finished run back.

REST API

Versioned endpoints under /api/v1/* with Bearer-key auth.

Read the docsAPI overview

MCP server

run_goal and 36 more tools for Cursor, Claude Desktop, Claude Code and Cline.

Set up the MCP serverSee pricing

Hand it a task

Type what you want done. Starting the run carries your task into a free account, where it runs live.

From your goal to a finished run

Everything between your goal and a finished run happens automatically, and gets cheaper every time it repeats.

  1. 01

    Goal received

    A plain-language goal comes in from the dashboard console, the REST API, or an MCP client.

  2. 02

    DOM compiled to an indexed map

    The live page compiles into a compact numbered map of what an agent can act on — no selectors to maintain.

  3. 03

    Checked against the cache

    A re-phrased request is vector-matched against skills already compiled for this host, on every request.

  4. 04

    Replayed, or compiled fresh

    Hit: a compiled skill runs by name, with zero LLM calls. Miss: the planner discovers the goal once and minimizes it, so the next request is a hit.

  5. 05

    Result delivered

    Extracted data, confirmed clicks, or downloaded files land back with your agent.

Cheaper than an agent on repeat. Always up to date.

An agent that reasons through every run pays the model every time. Twin pays it once, then keeps the task current on the live site.

A first run pays the model once; a re-phrased request matched from the cache costs roughly a fifth of that; a replay has no model in the loop. Rates are on the pricing page.

  • Works on the live site, every time

    It reads the page as it is now, not a script written last month. When a site changes, a saved path that no longer fits is caught, learned again and saved as a new version.

  • Knows where it is

    It tracks, per site, whether you are signed in and how far a task got, so a retry picks up where it stopped instead of starting over.

  • Learns from every run

    A route one team’s run discovers is there for the next one, and your values and logins never leave your account.

Delegation infrastructure, not a run button

The semantic cache, the cross-tenant corpus and the human gate ship as infrastructure: the part that is hard to run yourself.

Semantic cache, checked first

A re-phrased request matches a skill already compiled for that host, adapted to the new values.

Explore the cache

A corpus that compounds

A skill compiled once by anyone is available to everyone; your values and credentials never cross a tenant boundary.

Explore the corpus

A human gate, not a guess

An approval or an MFA prompt pauses the run at that step; you approve from the live console and it resumes.

Explore the handoff

Put your agent to work. You keep the controls.

Start freeRead the docs

Built for every team that delegates

The compile, cache and replay layer is the same for everyone. What changes is the guardrails you set on top.

Use caseAI agentsGive your AI agent a real browser it can drive — reach any site, act under your guardrails, and let repeated work replay at near-zero cost.Use caseRPA replacementReplace brittle, selector-keyed RPA bots with skills that adapt to the page — you authorize the run, the agent does the work.Use caseQA & test automationAuthor end-to-end tests as goals, run them deterministically, and replay every failure as session video.Use caseData extraction at scaleExtract from authenticated, multi-step pages you're authorized to reach — the agent signs in, does the work, and replays repeat pulls at near-zero cost.Use caseInternal workflow automationAutomate the internal tools and vendor portals that have no API — with audit logging and human approval built in.Use caseAccessibility automationDrive web tasks on a user’s behalf and audit pages for accessibility — over a token-efficient view of the live DOM.

Authorized automation, by construction

The guardrails are enforced in the same request path every run takes.

The run URL is the authorization

Every call is authenticated with your key and acts on exactly the target you gave it. You hold the authorization, and it is stamped into the record.

Default-deny row-level security

Tenancy is enforced in Postgres, not only in the application. Every row is isolated by tenant with row-level security on by default.

Credential vault

Secrets are encrypted at rest, filled only at run time, and redacted from every log. Per-tenant keys, never shared.

Full audit log

Every run records its goal, its path, its success condition, and the target it acted on.

Twin will

  • First-party sites and accounts you connect
  • Operator-approved automation and internal RPA
  • Accessibility tooling and authorized testing

Twin won't

  • Getting into sites or accounts you have no right to use
  • Fake accounts, mass sign-ups or spam
  • Running without your API key and target URL
How we keep it safe

Questions, answered

The short, honest answers on how the delegation engine works.

All questions

Or email us.

What Twin Browser is

What is Twin Browser?
An AI agent that lives in the cloud and works for you in its own real browser. Hand it a plain-language task and it reaches the site, pulls the data and signs into the accounts you connect — inside the guardrails you set, and asking you before anything you would want to decide. It keeps going after you close the tab, and repeated tasks compile into skills that replay without the model, so they cost a fraction of the first run.
Will sites block it as a bot?
It browses like a person: curved pointer paths and human typing on every run, a residential exit with the browser’s language and timezone matched to it, and — when a site pushes back — a stealth browser that is real Chrome with the automation tells removed (Pro plan). A reputation wall that no browser passes comes to you once as a sign-in, which later runs reuse. It is for sites and accounts you are allowed to use: every run carries your key, its target and an audit record.
How do I call it?

Four ways in, pick whichever fits your stack:

  • REST API— versioned /api/v1/* endpoints, Bearer-key auth
  • MCP server— run_goal and 36 more tools — Cursor, Claude Desktop, Claude Code, Cline
  • LangChain / AutoGen— one-line tool adapters
  • Dashboard console— no code required

How it works & what it costs

Why does cost fall the more my agents run?

Most browser infrastructure re-runs the LLM on every execution, so cost climbs with usage. Twin pays the model once at cold compile, serves re-phrased requests from the semantic cache at roughly a fifth of that, and replays compiled skills with no model in the loop — marginal cost per run trends toward zero.

Cold compilemodel runs once
Cache hitrephrased request, ~1/5 cost
Compiled replayno model in the loop
What is the cross-tenant skill corpus?
Sanitized skill skeletons are reused across tenants, so your cache-hit rate climbs as more teams automate the same hosts. The skeleton is the route, not the data: your values, your credentials, and your exact paths never cross a tenant boundary.
What does it cost?
Usage-based credits, with an entry plan and a free tier to start. Each call is billed the higher of its flat action price or the metered cost of that run, against a public rate card at /api/v1/pricing. Pay-as-you-go auto top-up keeps a run from stopping partway because a balance ran out.

Built for agent builders

Run your first goal in a real browser

Free to start. Connect an account, set the guardrails, and hand off the busywork from MCP, REST or the hosted dashboard.

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