Automate a browser

Configure Chromium or Firefox in a Modal desktop and open a page.

Choose a browser image profile when the desktop needs Chromium or Firefox.

Configure Chromium

from modal_computer_use import (
    BrowserConfig,
    ComputerConfig,
    ComputerSandbox,
    ResourceConfig,
)

config = ComputerConfig(
    resources=ResourceConfig(profile="browser"),
    browser=BrowserConfig(kind="chromium"),
)

with ComputerSandbox.create(config=config) as computer:
    result = computer.browser.open_url("https://example.com")
    if not result.ok:
        raise RuntimeError(result.message)

    screenshot = computer.screenshots.full()
    screenshot.save("example.png")

Set kind="firefox" to use Firefox.

Prewarm the browser

Set prewarm=True when browser startup is part of a measured bottleneck:

from modal_computer_use import BrowserConfig, ComputerConfig, ResourceConfig

config = ComputerConfig(
    resources=ResourceConfig(
        profile="browser",
        cpu=4,
        memory_mib=8192,
    ),
    browser=BrowserConfig(kind="firefox", prewarm=True),
)

Prewarm starts the configured browser during desktop startup. It does not make a page ready for application use. Check the state that your task requires after you open the URL.

Inspect browser state

status = computer.browser.status()
metrics = computer.browser.render_metrics(
    "https://example.com",
    timeout_seconds=30.0,
)
print(status)
print(metrics)

status() returns daemon browser state. render_metrics() opens the URL and returns the measured browser result. Render metrics require Chromium in version 1.1.0.

Use desktop primitives

The browser namespace handles browser lifecycle operations. Use the normal input and observation namespaces for page interaction:

computer.mouse.click(320, 240)
computer.keyboard.hotkey("CTRL", "L")
computer.keyboard.type("https://example.com")
computer.keyboard.press("ENTER")
screenshot = computer.screenshots.full(show_cursor=True)

Keep provider model loops in your application. Modal Computer Use provides provider adapters, but the core package does not call model APIs.