The Modal Context Protocol (MCP), a widely used AI protocol, transitioned from using HTTP+Server-Sent Events (SSE) to Streamable HTTP for its transport mechanism as of protocol version 2025-03-26, marking a significant shift in its architecture. This change was driven by the limitations of HTTP+SSE, such as the lack of support for resumable streams, the requirement for long-lived connections, and unidirectional communication, which hindered efficient real-time communication. Streamable HTTP addresses these issues by supporting stateless communication and optional SSE upgrades, enhancing compatibility with modern infrastructure and ensuring more stable and efficient data transmission. Despite this transition, MCP maintains backward compatibility with SSE-based systems, allowing for a smoother adoption process for third-party MCP clients and servers. The new transport protocol offers improved scalability, infrastructure compatibility, and optional streaming capabilities without requiring always-on connections, making it better suited to the needs of real-time AI communications. The MCP protocol continues to evolve, and developers are encouraged to stay updated with future developments through the MCP GitHub repository and official website.