MCP OAuth 2.1 Authentication: How AI Agents Securely Connect to Tools
The Model Context Protocol (MCP) defines how AI agents connect to external tools and data sources. When an MCP client (like Claude Desktop or a custom AI agent) needs to access a protected MCP server, it uses OAuth 2.1 — not OAuth 2.0 — as the authorization mechanism. This article explains exactly how MCP authentication works, what makes it different from traditional OAuth, and which identity providers actually support it. ...