Build "Sign in with Your App" using Supabase Auth

Supabase has enhanced its authentication capabilities by integrating OAuth 2.1 and OpenID Connect into Supabase Auth, allowing projects to function as full-fledged identity providers. This development opens up various opportunities, such as AI agents authenticating through the Model Context Protocol (MCP), facilitating secure third-party developer integrations, enabling enterprise single sign-on, and offering granular access control. The implementation seamlessly integrates with existing Supabase Auth features, leveraging methods like password authentication, magic links, and social providers, while complying with modern security standards, including PKCE and JWT-based access tokens. The integration supports Row Level Security (RLS) policies and extends to OAuth clients, enabling secure and customizable access to user data. Supabase Auth provides an OIDC discovery endpoint, facilitating easy integration with enterprise systems, while ongoing improvements include refining granular permissions and enhancing MCP server development directly within Supabase, fostering an open development environment.