Most browser automation runs from the outside. Playwright, Puppeteer, Selenium, and browser-use all drive a browser from an external process. They read the page through screenshots or the Chrome DevTools Protocol. Alibaba’s Page Agent takes the opposite path. The agent lives inside the webpage as plain JavaScript. It reads the live DOM as text and acts as the real user. No headless browser, no screenshots, no multi-modal model. The project is open-source under the MIT license. The codebase is Ty