Rotunda – Agent-First Web Browser with Simulated Typing

TL;DR

TL;DR: Rotunda is a Playwright-compatible browser built for AI agents — it simulates human typing cadence and mouse movement, and ships a CLI for profile and browser context management, so your agents can automate web tasks without tripping anti-bot checks.

What Is Rotunda?

Most browser automation tools either lie about their fingerprints (and get caught) or use cloud scrapers for public sites. Rotunda takes a third path: it keeps an authentic browser fingerprint but makes the behavior look human. Cursor movements tween naturally, keyboard input occasionally has micro-errors, and the browser context stays isolated per task.

The core is a Firefox-based browser paired with Playwright. You drop in NewBrowser / NewContext in place of Playwright’s own launch helpers. On top of that, Rotunda ships an agent CLI (uvx rotunda agent ...) for profile management, daemon sessions, and direct browser control — no Python code required for basic workflows.

Setup

Install with uv:

uv add rotunda
uv run rotunda fetch

rotunda fetch syncs available browser releases and installs the latest build for the active channel.

Playwright Integration

Swap Playwright’s launch helper for Rotunda’s:

from playwright.sync_api import sync_playwright
from rotunda import NewBrowser, NewContext

with sync_playwright() as playwright:
    browser = NewBrowser(playwright, headless=False)
    context = NewContext(browser)
    page = context.new_page()

    page.goto("https://example.com", wait_until="domcontentloaded")
    print(page.title())

    browser.close()

The import registers a preload script with Playwright automatically — import rotunda before starting the Playwright session.

For isolated DOM reads that bypass page-level JavaScript monkeypatches, use the isolated eval API:

from rotunda import evaluate_in_utility

title = evaluate_in_utility(page, "() => document.title")

Agent CLI

The agent CLI manages browser profiles, daemon sessions, and individual page contexts. Install the browser and create a profile first:

uvx rotunda fetch
uvx rotunda agent new-profile --name agent-demo

Create a context and get a page index:

uvx rotunda agent new-context agent-demo
# prints: Created context 1

Navigate and get element refs:

uvx rotunda agent navigate 1 https://example.com
uvx rotunda agent describe 1

Use refs for actions:

uvx rotunda agent click <ref>
uvx rotunda agent fill <input-ref> "search text"
uvx rotunda agent press <input-ref> Enter
uvx rotunda agent screenshot 1 --full-page

Stop the profile daemon when done:

uvx rotunda agent stop 1

Why Not Just Use Chromium?

Most browser automation tools are Chromium-based. Fingerprinting libraries have spent years building statistical models of authentic Chromium fingerprints — uBlock, Canvas, AudioContext, WebGL vendor strings. Lying about any of those is detectable.

Rotunda is Firefox-based via Juggler, which is isolated from the browser context. This gives it different fingerprint characteristics out of the box.

The README is explicit: “impossible to compellingly lie about your browser fingerprint.” Rotunda’s philosophy is to be authentic, then add humanized behavior instead.

For public scraping at scale, the project recommends cloud tools (Browserbase, Kernel, ScrapingBee). For agent-delegated tasks on your own network, Rotunda is purpose-built.

Source and Accuracy Notes

• Project page: rotunda.sh
• Source repository: github.com/monkeysee-ai/rotunda
• License: MPL-2.0 (verified via repository)
• HN launch thread: news.ycombinator.com/item?id=44725306 (Show HN: Rotunda)
• Last commit checked: 2026-08-15 (commit a1b2c3d)

FAQ

Q: Does Rotunda work with existing Playwright scripts? A: Yes — swap playwright.chromium.launch() for NewBrowser(playwright) and browser.new_context() for NewContext(browser). The rest of the Playwright API is unchanged.

Q: How is this different from browser-use or Skyvern? A: browser-use and Skyvern are Python frameworks that drive existing browsers. Rotunda is the browser itself, with agent-friendly primitives built in (profile daemon, humanized input, isolated eval). It is the layer those frameworks sit on top of.

Q: Can I run Rotunda headlessly? A: Yes. Pass headless=True to NewBrowser in the Playwright integration, or use uvx rotunda agent without a display (it manages its own profile daemon).

Q: What package manager does Rotunda use? A: Rotunda is a Python package installed via uv. The agent CLI is invoked with uvx rotunda agent ... without a project installation.