Use this skill ANY time you write, debug, run, audit, extend, or even *think about* Playwright E2E tests in Nicolify. Activate when the user mentions: 'smoke test', 'e2e', 'playwright', 'tests E2E', 'agreguemos un smoke', 'el smoke falla', 'auth de Clerk en tests', 'test:e2e', 'spec.ts', 'storageState', 'auth.fixture', 'POM', 'page object', 'browser test', 'test integral', 'preflight', 'test que abra el navegador', 'verificar el flujo X end-to-end', 'CI de Playwright', 'fixtures de Playwright', '/test-all flake', 'playwright report', 'trace viewer', 'visual regression Playwright', 'verify project', 'Clerk testing token', 'CLERK_TESTING_TOKEN', 'playwright/.clerk/user.json', 'Bot traffic detected', 'Clerk Frontend API URL is required', 'session expired Playwright'. ALSO trigger proactively before any commit/PR that touches `frontend/e2e/**` or any UI flow that could affect smoke tests, and before any GH Actions change to `e2e-tests.yml`. Covers: Clerk auth lifecycle (testing token + storageState + freshness gate + retry + sanity check), Page Object Models, network mocking with `page.route`, multi-tenant fixture, sharding, flaky-test debugging via trace viewer, and Nicolify-specific anti-patterns (NEVER `make e2e*` Docker — crashes the laptop). When in doubt, USE this skill — under-triggering Playwright knowledge is the #1 cause of broken E2E suites in this codebase.