> ## Documentation Index
> Fetch the complete documentation index at: https://browseruse-0aece648-mintlify-cli-docs-1773354647.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Basics

> Low-level Playwright-like browser automation with direct and full CDP control and precise element interactions

## Core Architecture

```mermaid theme={null}
graph TD
    A[Browser] --> B[Page]
    B --> C[Element]
    B --> D[Mouse]
    B --> E[AI Features]
    C --> F[DOM Interactions]
    D --> G[Coordinate Operations]
    E --> H[LLM Integration]
```

### Core Classes

* **Browser** (alias: **BrowserSession**): Main session manager
* **Page**: Represents a browser tab/iframe
* **Element**: Individual DOM element operations
* **Mouse**: Coordinate-based mouse operations

## Basic Usage

```python theme={null}
from browser_use import Browser, Agent
from browser_use.llm.openai.chat import ChatOpenAI

async def main():
    llm = ChatOpenAI(api_key="your-api-key")
    browser = Browser()
    await browser.start()

    # 1. Actor: Precise navigation and element interactions
    page = await browser.new_page("https://github.com/login")
    email_input = await page.must_get_element_by_prompt("username field", llm=llm)
    await email_input.fill("your-username")

    # 2. Agent: AI-driven complex tasks
    agent = Agent(browser=browser, llm=llm)
    await agent.run("Complete login and navigate to my repositories")

    await browser.stop()
```

## Important Notes

* **Not Playwright**: Actor is built on CDP, not Playwright. The API resembles Playwright as much as possible for easy migration, but is a subset.
* **Immediate Returns**: `get_elements_by_css_selector()` doesn't wait for visibility
* **Manual Timing**: You handle navigation timing and waiting
* **JavaScript Format**: `evaluate()` requires arrow function format: `() => {}`