playwLeft

Agent-first browser automation toolkit built in Rust.

playwLeft is a high-performance browser automation library designed primarily for AI agents and programmatic use cases. Built in Rust with Python bindings, it provides a powerful interface for browser testing, web scraping, and data extraction — without the overhead of visual tooling.

Key Features

• Agent-First Design — Optimized for machine-readable output, structured data extraction, and headless operation. No screenshots, video recording, or GUI inspectors.
• Rust Core — High performance, low memory footprint, strong type safety.
• Python Library — Distributed as a Python package with both sync and async APIs.
• CDP Protocol — Direct Chrome DevTools Protocol communication for precise browser control.
• Structured Extraction — Built-in methods to extract text, links, tables, and structured data from pages.

Architecture

┌─────────────────────────────────────────────────┐
│                 Python API Layer                 │
│            (sync_api / async_api)                │
├─────────────────────────────────────────────────┤
│              PyO3 Bindings Layer                 │
├─────────────────────────────────────────────────┤
│                 Rust Core                        │
│  ┌──────────┐ ┌──────────┐ ┌──────────────────┐ │
│  │ Browser  │ │  Page    │ │    Network       │ │
│  │ Manager  │ │  & Frame │ │  Interception    │ │
│  └────┬─────┘ └────┬─────┘ └───────┬──────────┘ │
│       │             │               │            │
│  ┌────┴─────────────┴───────────────┴──────────┐ │
│  │           CDP Protocol Layer                │ │
│  │    (WebSocket Transport + Sessions)         │ │
│  └─────────────────────────────────────────────┘ │
├─────────────────────────────────────────────────┤
│              Chromium Browser Process             │
└─────────────────────────────────────────────────┘

Quick Start (Python)

import asyncio
from playleft import PlaywLeft

async def main():
    async with PlaywLeft() as pw:
        browser = await pw.chromium.launch()
        page = await browser.new_page()

        await page.goto("https://example.com")

        # Get page content
        title = await page.title()
        content = await page.content()

        # Agent-optimized: extract structured data
        text = await page.extract_text()
        links = await page.extract_links()

        # Network interception
        await page.route("**/*.css", lambda route: route.abort())

        # JavaScript evaluation
        result = await page.evaluate("document.title")

        await browser.close()

asyncio.run(main())

Installation

pip install playleft

Class Hierarchy

Class	Description
PlaywLeft	Entry point — provides browser type access
BrowserType	Launches or connects to browser instances
Browser	A browser instance with context management
BrowserContext	Isolated browser session (like incognito)
Page	A single browser tab with full interaction API
Frame	An iframe within a page
Element	A DOM element with query and action methods
Request	Outgoing network request
Response	Incoming network response
Route	Network request interception handler

Design Principles

1. Responses over Rendering — Every API returns structured, machine-parseable data.
2. Headless by Default — No headed mode; all interactions are programmatic.
3. Minimal Surface — Only the APIs agents actually need, no legacy compat.
4. Performance First — Rust core ensures minimal latency and memory usage.
5. Deterministic — Consistent behavior across runs, no flaky waits.

License

Apache-2.0