In the rapidly evolving landscape of AI coding agents, the transport layer has emerged as a critical factor in determining the efficiency and performance of these tools. This article delves into the importance of stateful continuation for AI agents, particularly in the context of transport layers, and explores how this innovation can significantly enhance the speed and efficiency of agentic coding workflows. By examining the 'Airplane Problem' and the 'Agentic Coding Loop', we uncover the challenges posed by stateless APIs and the transformative potential of stateful continuation. Through a detailed analysis of benchmarks, we validate the performance gains achieved by WebSocket mode, which caches conversation history server-side, reducing client-sent data by up to 86% and improving execution time by 15-29%. The article also explores the broader implications of this technology, including its impact on API compatibility, protocol overhead at scale, server-side state management, and the statefulness spectrum. Finally, we discuss the trade-offs and considerations for architects building agentic systems, emphasizing the importance of recognizing the evolving role of the transport layer in AI agent development.