Worked on the modelcontextprotocol/go-sdk repository to address a critical issue in JSON-RPC message handling, focusing on backend development and API reliability using Go. Delivered a targeted fix that ensures messages with an empty method key are correctly interpreted as requests, preventing valid payloads from being dropped by stdio servers. The solution involved implementing a single-pass decode path with json.RawMessage for the method field, which reduced parsing overhead and aligned with JSON-RPC semantics. Comprehensive regression tests and conformance checks were added, resulting in full server and client protocol validation and improved error handling for robust JSON handling in backend systems.