MCP's 2026-07 spec replaces sampling/elicitation with Multi Round-Trip Requests (SEP-2322)

Model Context Protocol Blog·medium signal

The 2026-07-28 MCP specification release candidate introduces SEP-2322 Multi Round-Trip Requests, which supersedes server-initiated sampling and elicitation: a server returns an InputRequiredResult carrying inputRequests plus an opaque requestState, the client gathers the answers, and re-issues the original call with inputResponses. This makes server-driven human-in-the-loop and mid-task LLM reasoning stateless and easier to proxy. MCP builders should plan migration now — code written against the old sampling/elicitation callbacks will need to move to the request/state/response round-trip model.