Nomotic, Inc. AI agents and agentic systems generate a growing volume of intent- driven, unstructured, and undifferentiated traffic that flows through HTTP indistinguishably from human-initiated requests. HTTP lacks the semantic vocabulary, observability primitives, and identity mechanisms required by agent systems operating at scale. Existing protocols described as "agent protocols" including MCP, ACP, A2A, and ANP, are messaging-layer constructs that presuppose HTTP as their transport. They do not address the underlying transport problem. This document defines the Agent Transfer Protocol (AGTP): a dedicated application-layer protocol for AI agent traffic. AGTP provides agent-native intent methods (QUERY, SUMMARIZE, BOOK, SCHEDULE, LEARN, DELEGATE, COLLABORATE, CONFIRM, ESCALATE, NOTIFY), protocol-level agent identity and authority headers, and a status code vocabulary designed for the conditions AI agent systems encounter. AGTP SHOULD prefer QUIC for new implementations and MUST support TCP/TLS for compatibility and fallback. It is designed to be composable with existing agent frameworks, not to replace them.