If you're building a REST API with Fastify and need to validate JWT access tokens from Auth0, this handles the JWT verification middleware so you don't have to roll your own. It's specifically for stateless API authentication where your frontend or mobile app sends a Bearer token with each request. The setup is straightforward: register the plugin with your Auth0 domain and API audience, then protect routes with `fastify.requireAuth()`. One gotcha worth knowing upfront is that you need to create an API resource in Auth0, not just an Application, and clients must request access tokens with the correct audience parameter. If you're building a server-rendered web app with sessions instead, you want the regular auth0-fastify skill, not this one.
npx skills add https://github.com/auth0/agent-skills --skill auth0-fastify-api