MCP Dev Summit NYC draws 1,200 attendees - stateless transport and MCP Apps take center stage

The Agentic AI Foundation held its first MCP Dev Summit on April 2-3 at the New York Marriott Marquis, drawing roughly 1,200 attendees. The two-day event made clear that MCP has moved well past its experimental phase and into production infrastructure.

David Soria Parra, MCP co-creator and Anthropic staff member, delivered the opening keynote. He traced the protocol's evolution from local stdio-only servers to today's landscape of remote servers, authorization, structured outputs, and the experimental tasks primitive for long-running agent communication. The talk laid out a roadmap that prioritizes stability and scalability over new features.

The biggest technical thread was SEP-1442, which proposes moving MCP from stateful sessions toward stateless requests. This matters because stateful sessions fight with load balancers and make horizontal scaling painful. The new approach would let MCP servers scale without holding session state, which is a major barrier for anyone running MCP in production today. The working group presented early implementation results showing that stateless mode reduces connection overhead by roughly 60% in multi-server deployments.

MCP Apps got significant attention throughout the summit. The extension, officially released in January 2026 under SEP-1865, lets MCP servers deliver interactive UIs (HTML, JavaScript, CSS) rendered in sandboxed iframes. Within months of launch, MCP Apps had been adopted by Claude, ChatGPT, VS Code with GitHub Copilot, Goose, Postman, and MCPJam. Several talks demonstrated practical applications, from data visualization dashboards to approval workflows built entirely as MCP Apps.

Duolingo shared a case study on how they went from a handful of engineers experimenting with MCP to 250 weekly active users internally. Their setup routes language-learning content management through MCP servers, letting product managers update exercises using natural language. Amazon and Uber also presented production deployment stories, focusing on security patterns and horizontal scaling challenges at their respective scales.

Jim Zemlin, Linux Foundation executive director, highlighted the rapid growth of the AAIF since its December 2025 formation. The foundation has already added over a hundred members across Platinum, Gold, and Silver tiers, including AWS, Microsoft, Google, Bloomberg, and Cloudflare.

For anyone building with MCP, the summit signals that the protocol is entering its enterprise hardening phase. The transport changes, security improvements, and governance maturation all point toward MCP becoming stable production infrastructure rather than a fast-moving experiment. Recordings of the keynotes and technical talks are expected to be published on the AAIF website in the coming weeks.