Agent skill · chromedevtools
cookie-debugging
Uses Chrome DevTools MCP for inspecting, debugging, and testing cookies, session state, authentication issues, and cookie consent compliance. Use when diagnosing 401/403 errors, authentication redirects, session expiration, Cookie/Set-Cookie header issues, cookie banner consent conformance, or third-party cookie/SameSite/Partitioned cookie warnings.
What it needs
About 5k tokens when loaded.
What this skill does
Core Concepts HttpOnly vs Client-Side Storage Cookies marked HttpOnly cannot be accessed or modified by client-side JavaScript (cookieStore or document.cookie). However, the browser automatically attaches active HttpOnly cookies to outgoing HTTP request headers (Cookie). To inspect current HttpOnly values: Look at the Cookie request header of any outgoing HTTP request via getnetworkrequest. To inspect how cookies were created or configured: Look at the Set-Cookie response header of login/auth responses. To inspect non-HttpOnly cookies: Use evaluatescript with the modern cookieStore API (async () => await cookieStore.getAll()). Session Strategy: Live Tab vs Isolated Context Choose the right session environment to avoid state contamination (e.g., residual analytics or auth tokens): Strategy When to Use Setup / Teardown :---------------------------------- :---------------------------------------------------------------------------- :------------------------------------------------------------------------------------------------------------ Live Tab (Active Page) Diagnosing an active user session, live 401/403 error, or current state. Operates directly on the currently selected page. Clean-Slate (isolatedContext) Testing cookie consent banners, first-time visits, or zero-cookie guarantees. Call newpage with a unique isolatedContext (e.g. "consent-audit-1"). When finished, call closepage. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills chromedevtools/cookie-debugging