Browser Runtimes

Browser runtimes are hosted Chromium environments inside a space. BCTRL runs the browser, manages access, records evidence, and gives your automation code a CDP connection.

Your external automation tools connect over CDP:

• Playwright
• Puppeteer
• Selenium
• Chrome DevTools-compatible debuggers

Hosted AI work uses invocations instead. Use invocations when BCTRL should run Stagehand or browser-use agent work inside the runtime.

What BCTRL manages

Basic flow

1
const space = await bctrl.spaces.create({
2
  name: "invoice-agent",
3
});
4
5
const runtime = await space.runtimes.browser.launch({
6
  name: "quickbooks",
7
  config: {
8
    stealth: "high",
9
  },
10
});
11
12
const connection = await runtime.connections.create({
13
  protocol: "cdp",
14
});

Pass connection.endpoint.url to your browser framework and run normal automation code.

1
const browser = await chromium.connectOverCDP(connection.endpoint.url);
2
const page = browser.contexts()[0]?.pages()[0] ?? await browser.newPage();
3
4
await page.goto("https://example.com");

Observe the active run through currentRun().

1
const run = await runtime.currentRun();
2
3
await run.events.list();
4
await run.artifacts.list();

Related

• Browser Quickstart
• Connect with CDP
• Runs