Update README.md

Author: hrntknr

README.md

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 # MCP Auth Proxy
 
-MCP Auth Proxy is a secure OAuth 2.0 authentication proxy for Model Context Protocol (MCP) servers. MCP servers are expected to support not only standard OAuth 2.0 flows but also Dynamic Client support (e.g., dynamic client registration) and authentication-related .well-known metadata. On top of that, different MCP clients handle tokens differently, which makes implementation tricky.
+MCP Auth Proxy is a secure OAuth 2.1 authentication proxy for Model Context Protocol (MCP) servers. MCP servers are expected to support not only standard OAuth 2.1 flows but also Dynamic Client support (e.g., dynamic client registration) and authentication-related .well-known metadata. On top of that, different MCP clients handle tokens differently, which makes implementation tricky.
 
 MCP Auth Proxy sits in front of your MCP services and enforces sign-in with OAuth providers (such as Google or GitHub) before users can access protected MCP resources.