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MCP 2026-07-28 drops stateful sessions and adds required routing headers for gateway control
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The MCP 2026-07-28 specification removes the initialize handshake and session tracking, making each request self-contained, and adds mandatory Mcp-Method and Mcp-Name headers so gateways can route and throttle agent traffic without parsing JSON bodies.
This removes the infrastructure burden of session persistence that made load balancing and autoscaling impractical for MCP, but the community split reflects a real question: the protocol now looks functionally indistinguishable from a REST API with an OpenAPI-style spec. For operators, the routing headers mean existing API gateway and WAF tooling works on agent traffic without custom parsing.
Written by elseif from the cluster below · every claim links back to a sourceThe three things worth knowing
The specification removes the initialize handshake, Mcp-Session-Id header, and protocol sessions, so any request can land on any instance.
Two mandatory headers (Mcp-Method and Mcp-Name) let gateways route, throttle, and meter traffic by method or tool name without parsing the JSON-RPC body.
Elicitation shifts from a held connection to a two-request retry pattern, and Dynamic Client Registration is deprecated with removal planned after summer 2027.
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