4/24/2025

The Journey of Building a Comprehensive MCP: Lessons Learned

Building a Model Context Protocol (MCP) server may seem like an uncharted territory, but the journey is one filled with lessons, growth, and innovation. From the inception of the Model Context Protocol to creating robust connections between LLMs (Large Language Models) and tools or data, navigating this landscape has been nothing short of exhilarating.

What is Model Context Protocol?

The Model Context Protocol serves as a universal language that facilitates communication between artificial intelligence (AI) models and external tools, data, and applications. It’s like a USB-C connector for AI applications—it provides a standardized way to integrate various components seamlessly.

In this post, we’ll explore the complexities of building a comprehensive MCP, focusing on the valuable lessons we’ve learned throughout this fascinating expedition.

Understanding the Core Architecture

At its heart, MCP follows a client-server architecture that comprises:

MCP Hosts: This includes programs, applications, or tools that require LLM interaction.
MCP Clients: The protocol clients that maintain a direct link to the servers and handle the requests made by users.
MCP Servers: Lightweight yet powerful programs that expose specific capabilities compliant with the MCP standard.
Local Data Sources: These can be accessed directly by servers from local files or databases.
Remote Services: External APIs and tools that the servers may connect to.

Lesson 1: Focus on Clarity in Design

Throughout our journey, we learned the importance of clarity in our design. The initial iterations of the MCP server were often plagued by vague definitions and ambiguous functionalities. This lack of clarity not only confused developers but also made onboarding new team members a Herculean task. By adopting a clear and concise architecture model early on, we mitigated possible development bottlenecks and improved communication among stakeholders.

The Development Toolkit: Selecting the Right Technologies

Choosing the right technologies and tools is crucial to ensure a seamless development experience. We explored various SDKs including:

Python SDK
TypeScript SDK
Java SDK
Kotlin SDK
C# SDK

Lesson 2: Embrace Open Source

One of the most liberating aspects of building the MCP was embracing the open-source community. This leverage allowed us to tap into existing solutions and methodologies, significantly speeding up our development cycle. Participating in communities not only helped us gain access to robust tools but also provided a platform to share and receive feedback on our progress.

Building and Testing the Core Functionality

Once we had a clear architecture in place and the tools were set up, we began coding our core functionalities. This phase was vital since it involved:

Establishing essential APIs
Developing key features such as resource management, tool definitions, and prompt templates
Integrating error handling and logging mechanisms

Lesson 3: Start Small, Iterate Often

Mistakes were made, as expected when coding the functionalities. Initially, we attempted to build a fully functioning server in one go, only to be met with numerous issues. We learned the value of starting with minimal functionality, launching it, and then iteratively adding features based on user feedback and testing outcomes. This approach saved us countless man-hours and helped us prioritize functionality that delivered real value to users.

Ensuring User Engagement with Custom Tools

A key aspect of MCP is its ability to leverage custom tools tailored to specific needs. For instance, integrating Claude, a frontier LLM, provided us with numerous advantages, such as:

Creating tailored prompts that allow the system to deliver highly relevant outputs.
Developing user interfaces that enhance interaction without overwhelming end-users.

Lesson 4: User Experience is Everything

One of our greatest revelations stemmed from testing the user experience. We realized that, while backend functionality is essential, the user interfaces and user interactions often determine success or failure. By involving our potential user base early in the design process and continually soliciting their input, we were able to create a user experience that customers felt passionately about.

Testing and Debugging: The Inevitable Hurdles

As with any comprehensive system, issues arose during testing and debugging. A well-developed MCP can be incredibly intricate due to its interactions with various APIs and tools, leading us into unanticipated challenges.

Lesson 5: Develop a Robust Debugging Framework

Initially, debugging processes were cumbersome and often led to dead ends. However, once we established a structured debugging framework, we observed significant improvements in our testing outcomes. MCP Inspector, a custom-built tool, was instrumental in logically inspecting server-state interactions and elucidating unexpected behaviors.

Collaboration within Teams

The development of the MCP required collaboration across different teams, including designers, backend programmers, and stakeholder management. Over time, we understood the dynamics of efficient teamwork.

Lesson 6: Foster an Environment of Open Communication

Encouraging open communication fueled our creative processes. Iteration on design documents, painless feedback sessions, and brainstorming groups significantly reduced silos between teams. This culture not only accelerated the development process but also drove a sense of collective ownership.

Launching the MCP: The Final Stretch

Finally, as we neared the launch date, the excitement built. This was a time to not only reflect on what we had accomplished but also prepare ourselves for potential hurdles ahead.

Lesson 7: Prepare for Post-Launch

Even though the launch felt like the end of the journey, we realized it was just the beginning. Comprehensive training for staff, ongoing technical support, and a plan for collecting user feedback became crucial components of the final phase. This mindfulness allowed us to pivot quickly based on user interactions and suggestions.

Continuous Improvement through User Feedback

After the launch, we felt it was essential to maintain user engagement with regular updates based on their feedback. Utilizing the lessons learned from the initial rollout, we continuously optimized and introduced new functionality tailored to evolving user needs. These upgrades ensured the MCP stayed relevant and valuable over time.

Lesson 8: Build a Feedback Loop

Ultimately, establishing a structured feedback loop became one of our most valuable assets post-launch. Not only did it facilitate immediate improvements, but it also helped chart a roadmap for future developments. Regular user surveys and analyzing engagement metrics were key to this iterative approach.

Conclusion: The Journey Continues

Building a comprehensive Model Context Protocol has been a journey filled with twists and turns, yet it's rich with learning and discovery. The MCP world is rapidly growing, and as technology continues to advance—including the emergence of Arsturn—the opportunities to harness this protocol will undoubtedly evolve.

Arsturn enables businesses to instantly create custom chatbots to enhance audience engagement before people even visit your website. With a no-code solution, it's adaptable, insightful, and fully customizable to your brand's needs. Whether it's handling FAQs, providing event details, or enhancing your customer service experience—Arsturn is here to help!

Dive into the MCP journey yourself, and who knows? You might just discover innovative ways to revolutionize the connection between AI and the real world!