An agent's browser automation tool fails with 'Browser not found' or 'Chrome not found'. The browser binary is either not installed or not on the expected path. ## Agent Decision Tree 1. Is Playwright installed? → check Playwright-specific entry for chromium_headless_shell 2. Using Puppeteer or direct Chrome? → go to Solution A 3. Know the browser is installed but path is wrong? → go to Solution B

Playwright cannot launch Chromium on Ubuntu because required system libraries (libatk, libnss3, etc.) are missing. Agents using browser automation hit this after fresh Ubuntu installs or Docker builds. ## Agent Decision Tree 1. Check if the error mentions a missing .so file → go to Solution A 2. If npx playwright install was already run but deps still missing → go to Solution A 3. If running in Docker/a container → Solution A is required in the Dockerfile