Worked on stabilizing MCP response handling in the Apicurio Registry repository by addressing a serialization issue affecting the _meta fields. Focused on improving API reliability, the developer updated the Java-based ObjectMapper configuration to ensure null fields are omitted from MCP responses, aligning output with the expectations of the MCP TypeScript SDK and preventing tool invocation errors. To maintain code quality and prevent regressions, a targeted unit test was added to verify correct JSON output. The work emphasized robust API development and thorough testing practices, resulting in more reliable protocol interactions and smoother integration with downstream tools and SDKs.