Lightpanda Browser

Lightpanda Browser

Use Lightpanda as the default AI-controlled browser for web retrieval and automation when graphical rendering is not required. It is a headless browser built for AI agents and automation, with JavaScript execution, CLI fetch, CDP, and native MCP interfaces.

Local Runtime

• CDP endpoint: http://127.0.0.1:9222
• WebSocket endpoint: ws://127.0.0.1:9222/
• MCP command: %USERPROFILE%\.lightpanda-ai\lightpanda-mcp.cmd
• Fetch command: %USERPROFILE%\.lightpanda-ai\lightpanda-fetch.cmd
• Start service: powershell -NoProfile -ExecutionPolicy Bypass -File "$env:USERPROFILE\.lightpanda-ai\lightpanda-serve.ps1"
• Stop service: powershell -NoProfile -ExecutionPolicy Bypass -File "$env:USERPROFILE\.lightpanda-ai\lightpanda-stop.ps1"

This is an AI-only browser runtime. It does not change the operating system default browser.

Selection Rules

1. Prefer Lightpanda for AI browsing, scraping, markdown extraction, semantic tree extraction, JavaScript-rendered content, link discovery, and form workflows.
2. Prefer the MCP interface for agent workflows when a Lightpanda MCP server is available.
3. Prefer the CLI fetch wrapper for one-off URL extraction: & "$env:USERPROFILE\.lightpanda-ai\lightpanda-fetch.cmd" --dump markdown https://example.com
4. Prefer the CDP service for Playwright or Puppeteer automation. Connect to http://127.0.0.1:9222 with connectOverCDP or to ws://127.0.0.1:9222/ when a WebSocket endpoint is required.
5. Use a full browser such as Chrome, Chromium, Playwright-managed browsers, or the host browser when the task requires screenshots, visual inspection, pixel/layout validation, browser extensions, WebGL/canvas fidelity, downloads, DevTools performance traces, or broad cross-browser compatibility.
6. Respect explicit user or system instructions that require a specific browser tool, local in-app browser, screenshot workflow, or official connector.

Playwright CDP Pattern

Use playwright-core or an existing Playwright install:

const { chromium } = require("playwright-core");

const browser = await chromium.connectOverCDP("http://127.0.0.1:9222");
const context = await browser.newContext();
const page = await context.newPage();
await page.goto("https://example.com", { waitUntil: "load" });
const text = await page.textContent("body");
await context.close();
await browser.close();

Puppeteer CDP Pattern

const puppeteer = require("puppeteer-core");

const browser = await puppeteer.connect({
  browserWSEndpoint: "ws://127.0.0.1:9222/"
});
const page = await browser.newPage();
await page.goto("https://example.com", { waitUntil: "networkidle0" });
const title = await page.title();
await browser.disconnect();

Limits and Compatibility

• Lightpanda is beta software. Fall back to a full browser when a site fails because of missing Web APIs or visual-rendering requirements.
• The upstream README says there is no native Windows binary. This profile uses Docker and exposes Lightpanda on localhost.
• Google commonly blocks Lightpanda by browser fingerprint. Use normal web search tools for search-engine queries unless a Lightpanda-specific extraction flow is needed.
• Docker-based MCP runs inside a container. For services on the Windows host, use host.docker.internal from inside the container if localhost does not refer to the intended target.
• The wrappers set LIGHTPANDA_DISABLE_TELEMETRY=true.

References

• Upstream browser README snapshot: UPSTREAM_README.md
• Upstream official agent skill snapshot: references/UPSTREAM_AGENT_SKILL.md
• Upstream agent skill README snapshot: references/UPSTREAM_AGENT_SKILL_README.md