Multimodal, Real-Time AI Agent Systems

Chapter 9. The Model Context Protocol (MCP): Standardizing Tool Interaction

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This will be the 10th chapter of the final book. Please note that the GitHub repo will be made active later on.

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In the previous chapters, we have built complete AI agents. We learned how to give them memory, an orchestration engine, and even how to connect them to custom-built tools. The systems we’ve created work, allowing an agent to call a function and get a result.

This approach is fine for a few simple tools. But what happens when we try to build more complex, production-ready systems? What happens when our agent needs to use ten tools, or a hundred? Our simple, custom-built connections start to create serious problems, turning our clean agent code into a fragile and unmanageable system.

This chapter is about moving from building isolated tools to creating a scalable ecosystem of tools. It’s about the difference between a custom solution that works for a demo and a professional, standardized architecture that works in the real world.

First, we will diagnose the specific problems that arise when we try to scale our current ...