Model Context Protocol (MCP) servers are often poorly built, which can lead to issues with AI agents underperforming due to unclear tool descriptions, ambiguous error messages, and varying authentication mechanisms. To prevent these issues, it is essential to comprehensively test an MCP server before using it in production, using sandbox data for every test to avoid risking sensitive information. Setting up a wide range of test scenarios that define expected behaviors and evaluating the tools' hit rates and success rates can help identify strengths and weaknesses of the MCP server's tools. Additionally, tracking unnecessary tool calls and using a third-party solution to run tests can help manage the complex and time-intensive process of testing an MCP server, ultimately ensuring that AI agents perform optimally and reducing potential errors and costs. By following best practices for testing MCP servers, developers can build more effective and efficient AI systems that integrate seamlessly with various tools and services.