Playwright and Puppeteer are browser automation libraries you embed in code. They drive pages through CSS selectors, which break whenever a site reshuffles its DOM.ego (lite) is a real browser plus ego-browser. ego-browser is the connection layer between any agent product (Claude Code, Codex, Cursor, or your own) and ego (lite) — it exposes the browser as a set of in-page JavaScript tools: snapshot, fill, click, wait, navigate, capture. The agent writes a JavaScript snippet that composes several steps using those tools, and ego-browser runs it on the page in one pass, instead of the one-tool-at-a-time round trips Playwright and Puppeteer require. The snapshots cost fewer tokens than HTML, and the @N refs stay stable when class names rotate. There's no SDK to integrate, and nothing to install from the Playwright or Puppeteer ecosystem.