AGNTCon + MCPCon Japan 2026

The MCP 2026-07-28 release candidate introduces a major shift in how agents connect, authenticate and manage state. With a stateless protocol core, first-class extensions and hardened authorization, the new spec improves scalability and interoperability, but it also changes the security model in ways that many builders may not fully anticipate. In this talk, I will examine the release candidate through a defender’s lens and highlight the practical risks that emerge when session state disappears, trust boundaries move and extension-based flexibility expands the attack surface. I will discuss failure modes such as broken state assumptions, capability confusion, unsafe cross-client behavior, and authorization mistakes in real deployments. The session will also cover concrete hardening patterns for secure MCP adoption, including least-privilege tool design, explicit state handling, authorization scoping, telemetry and rollout validation. Attendees will leave with a practical checklist for evaluating stateless MCP systems and defending agent runtimes in production.