MCP Gets Largest Update Yet, Sessions Abolished
The stateless redesign removes the operational burden of sticky sessions and shared session databases, making MCP viable for large-scale enterprise production environments, a shift that GitHub has already adopted ahead of the official release.
Key Facts
- The Model Context Protocol (MCP) released specification '2026-07-28' on July 28, 2026, its largest update since the protocol debuted in November 2024.
- The update abolishes protocol-level sessions and the 'initialize' handshake, shifting MCP to a stateless design where each request is self-contained.
- A 12-month minimum transition period is provided for deprecated features, including Roots, Sampling, Logging, and the old HTTP and Server-Sent Events communication method.
- Major SDKs for TypeScript, Python, Go, and C# support the new specification at release, with the Rust SDK in beta.
- GitHub MCP Server adopted the new specification ahead of the official release, removing Redis-based session storage.
Reporting from 1 source: GIGAZINE.
The Model Context Protocol (MCP), the open standard for connecting AI applications with external tools and data, received its largest update since its debut on July 28, 2026. The new specification, designated '2026-07-28', shifts MCP from a stateful to a stateless design, abolishing the session-based communication that required initialization and sticky sessions. This change allows each request to be self-contained, enabling MCP servers to be deployed and scaled on general HTTP infrastructure like Kubernetes, serverless, and edge environments. The update also introduces Multi Round-Trip Requests (MRTR) for handling user confirmations in stateless communication, revamps HTTP headers and caching, and moves long-running processing and screen display features into a formal extension mechanism. Authentication has been enhanced with mandatory validation of the 'iss' information in OAuth 2.0 and OpenID Connect, and Dynamic Client Registration has been deprecated in favor of Client ID Metadata Documents. A 12-month transition period is provided for deprecated features, including Roots, Sampling, Logging, and the old HTTP and Server-Sent Events communication method. Major SDKs for TypeScript, Python, Go, and C# support the new specification, with Rust in beta. GitHub MCP Server has adopted the new spec, and Anthropic plans to gradually introduce support to Claude products.
- MCP is developed under the Agentic AI Foundation within the AI Linux Foundation, after Anthropic proposed and open-sourced the protocol in November 2024.
- Application state is not lost in the stateless design: servers issue an identifier for state like shopping cart contents, and the AI agent passes it explicitly in the next tool call.
- MRTR works by having the server return an input_required result with the question content; the client adds the user's answer and re-sends the original request.
- HTTP headers now must include Mcp-Method and Mcp-Name, letting gateways, rate limiters, and web application firewalls route traffic without parsing the JSON body.
- The tool list order is fixed, which prevents prompt content from changing with each connection and invalidating caches.
- MCP Apps, which renders forms, tables, and dashboards inside chats, is delivered through the same extension mechanism as MCP Tasks.
- GitHub MCP Server removed its Redis session storage and the request-body processing logic when adopting the new spec.
- More than 950 MCP servers are registered in Claude's connector directory.
Synthesized by Yomimono from the 1 cited source below, including Japanese-language reporting where cited, then editorially reviewed before publishing.