17_MCP_A2A

Session 17: Model Context Protocol (MCP) & Agent-to-Agent (A2A) Protocol

Session Sheet	Recording	Slides	Repo	Homework	Feedback
MCP Servers & A2A	Recording! passcode: fJ9tx4h.	Session 17 Slides	You are here!	(Optional) Session 17 Assignment: MCP Servers & A2A	Feedback 3/12

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📚 Useful Resources

MCP (Model Context Protocol)

• MCP Official Docs — Spec, tutorials, and guides
• MCP-UI — Official standard for interactive UI in MCP
• MCP Auth Guide (Auth0) — Deep dive into MCP auth spec updates

A2A (Agent-to-Agent Protocol)

• A2A Official Docs — Spec and guides
• A2A GitHub Repo — Protocol spec and implementations
• Announcing A2A (Google Blog) — Protocol vision and motivation

MCP vs A2A

• A2A and MCP (Official) — How they complement each other

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Running the MCP Server

1. Install dependencies

uv sync

2. Set up environment variables

Copy the example env file and fill in your OpenAI API key:

cp .env.example .env

3. Run the MCP server locally

uv run server.py

The server will start on http://localhost:8000.

4. Expose the server with ngrok (for remote/Claude Desktop access)

In a separate terminal, start an ngrok tunnel:

ngrok http 8000

Copy the ngrok forwarding URL (e.g. https://xxxx-xx-xx-xx-xx.ngrok-free.app) and restart the server with it:

ISSUER_URL=https://xxxx-xx-xx-xx-xx.ngrok-free.app uv run server.py

Note: The ISSUER_URL must match the public URL clients use to reach the server, otherwise OAuth authentication will fail.

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Build 🏗️

In today's assignment, we'll be building an MCP server with OAuth authentication — a cat shop application that exposes tools for browsing products, managing a cart, and checking out.

• 🤝 Breakout Room #1

  • Set up the MCP server with OAuth and the product database
  • Explore the MCP tools: list_products, get_product, add_to_cart, view_cart, remove_from_cart, checkout

• 🤝 Breakout Room #2

  • Connect an MCP client to the server
  • Build an end-to-end interaction flow using the MCP tools

Ship 🚢

The completed MCP server and client integration!

Deliverables

• A short Loom of either:
  • the MCP server you built and a demo of the client interacting with it; or
  • the notebook you created for the Advanced Build

Share 🚀

Make a social media post about your final application!

Deliverables

• Make a post on any social media platform about what you built!

Here's a template to get you started:

🚀 Exciting News! 🚀

I am thrilled to announce that I have just built and shipped an MCP server with OAuth authentication! 🎉🤖

🔍 Three Key Takeaways:
1️⃣
2️⃣
3️⃣

Let's continue pushing the boundaries of what's possible in the world of AI and tool integration. Here's to many more innovations! 🚀
Shout out to @AIMakerspace !

#MCP #ModelContextProtocol #OAuth #Innovation #AI #TechMilestone

Feel free to reach out if you're curious or would like to collaborate on similar projects! 🤝🔥

Submitting Your Homework [OPTIONAL]

Main Homework Assignment

Follow these steps to prepare and submit your homework assignment:

1. Review the MCP server code in server.py and the app/ directory
2. Run the MCP server locally using uv run server.py
3. Connect to the server using an MCP client (e.g., Claude Desktop, or a custom client)
4. Test all available tools: browsing products, adding to cart, viewing cart, removing items, and checkout
5. Record a Loom video reviewing what you have learned from this session

Questions

❓ Question #1:

Why is OAuth important for MCP servers, and what security considerations should you keep in mind when exposing tools to AI clients?

✅ Answer:

(insert your answer here)

❓ Question #2:

What is the Agent-to-Agent (A2A) protocol, and how does it differ from MCP in terms of purpose and architecture? When would you choose A2A over MCP?

✅ Answer:

(insert your answer here)

Activity 1: Extend the MCP Server

Add at least one new tool to the cat shop MCP server (e.g., search_products, update_cart_quantity, or get_order_history). Ensure the new tool integrates properly with the existing database and OAuth authentication. Demo the new tool through an MCP client and include it in your Loom video.

Advanced Activity: Build a Custom MCP Client

Build a custom MCP client that connects to the cat shop server over Streamable HTTP, authenticates via OAuth, and orchestrates a multi-step shopping flow (browse → add to cart → checkout). Compare the developer experience of MCP-based tool integration vs. traditional REST API calls.

Include your findings and a demo in your Loom video.