AgentCore GatewayがMCP 2026-07-28仕様をサポートする方法How AgentCore Gateway supports the MCP 2026-07-28 spec

Amazon Web Services has published guidance on how its Bedrock AgentCore Gateway supports the Model Context Protocol (MCP) 2026-07-28 specification, which the protocol's maintainers describe as the largest revision since MCP launched. The change matters for developers building agentic systems, because MCP has become a widely used way to connect large language models to external tools, data sources, and services, and altering its foundations affects every client and server that relies on it.

At a high level, the new specification makes three notable changes: MCP is now stateless, it adds a governed extensions system, and it strengthens authorization. The AWS Machine Learning Blog post walks through what changed and shows how to enable the updated version on Amazon Bedrock AgentCore Gateway, positioning the managed service to remain compatible as the standard evolves.

MCP first appeared as an open protocol intended to standardize the connection between AI applications and the context they need, using a client-server model in which host applications talk to MCP servers that expose tools and resources. Before this revision, MCP interactions generally relied on persistent sessions, which required servers to track connection state across a series of requests. That approach worked but could complicate horizontal scaling, load balancing, and serverless deployment, where requests may be routed to different instances.

Making MCP stateless directly addresses those operational concerns. Without server-side session state to maintain, requests can in principle be handled independently, which tends to simplify deployment behind load balancers and on ephemeral compute. This is likely a meaningful change for cloud providers, since a stateless model aligns well with the managed, elastic infrastructure that AWS offers through Bedrock and Lambda.

The governed extensions system appears aimed at a recurring tension in fast-moving standards: allowing the protocol to grow without fragmenting into incompatible variants. A governed approach suggests a defined process for proposing, registering, and negotiating optional capabilities, so that vendors can extend functionality while clients and servers still agree on a common baseline. For an intermediary such as a gateway, that structure is useful because it clarifies which behaviors are standard and which are opt-in.

Hardened authorization continues a direction MCP has taken previously, when the protocol moved toward established patterns such as OAuth for delegated access. Strengthening authorization in the 2026-07-28 specification is consistent with growing scrutiny of how autonomous agents obtain and use credentials, given that an agent connected to many tools represents a broad potential attack surface. AWS lists authorization among the tags for the post, and AgentCore Gateway's role as a controlled entry point makes it a natural place to enforce these requirements.

Amazon Bedrock AgentCore is AWS's set of services for building and running agents