MCP Client OAuth Is Simpler Than You Think

Chris Hay

20 views • 8 months ago Save 17 min 2 min read

Video Summary

The video details the process of integrating OAUTH support into the MCP CLI tool, focusing on how the client protocol functions for client applications. It demonstrates this integration using Claude Code and a custom MCP CLI tool, showcasing the authentication flow with Notion. The process involves discovery of authorization endpoints, dynamic client registration, and user authorization via browser redirects, ultimately resulting in the acquisition of bearer tokens for secure API access.

This guide provides a comprehensive look at OAUTH integration for MCP client applications, from initial connection and authentication to secure token management and tool execution. The presenter offers practical code examples and a reusable library, simplifying the process for developers looking to build their own agents and applications.

Short Highlights

OAUTH Integration with MCP and Notion [00:00]

The video addresses the lack of information on how OAUTH works within MCP, especially for client applications.
It demonstrates OAUTH integration using Claude Code and a custom MCP CLI tool to connect with Notion.
The process involves configuring Notion as an MCP server, which initially requires authentication.
Users are guided through an authentication flow that includes selecting a workspace and granting permissions.
Upon successful authentication, the client can query Notion data, such as a list of upcoming videos.

So, in this video, I'm going to break down how the client protocol works.

Key Details

MCP CLI Tool and OAUTH Flow [03:17]

The presenter showcases the MCP CLI tool's OAUTH integration, which bundles the Notion server configuration.
Unlike traditional methods, the server configuration for MCP CLI does not contain sensitive tokens, as OAUTH handles authentication dynamically.
The initial step for the client is server discovery, where it queries the MCP server (e.g., notion.com/mcp) to understand how to authenticate.
The server responds with OAUTH endpoints and capabilities, allowing the client to locate the OAUTH server.

The first question when it goes and connects to your MCP server. So notion.com MCP then it's it's basically ask a question which is a question of discovery. How do I authenticate you?