Part 3: Testing, Deploying, and Lessons Learned

This is the final part of a three-part series on building an MCP server for healthcare interoperability, covering testing strategies, deployment workflows, and lessons learned. The team developed a three-layer testing approach including unit tests with temporary SQLite databases, URI testing, and end-to-end validation against AI clients. Key takeaways include challenges with module-level state in Python, the importance of graceful error handling for AI consumers, and architectural improvements they would make in hindsight.