Auth0‑Auth‑JS is a monorepo that provides a set of JavaScript SDKs (`auth0-auth-js`, `auth0-api-js`, and `auth0-server-js`) for adding Auth0‑powered authentication and authorization to client‑side, API, and server‑side JavaScript applications. It’s aimed at developers building web, mobile, or server applications who need a ready‑made, well‑documented library to handle login flows, token management, and API protection with Auth0.