SEP-2322: Multi Round-Trip Requests - #2322
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…emove garbage file
…uestParams — now available on any
client-initiated request, not just tool calls
2. Added typed InputResponse = ElicitResult | CreateMessageResult — InputResponses values are now properly typed
instead of { result: { [key: string]: unknown } }
3. Updated examples — removed the extra result wrapper from TaskInputResponseRequest and
TaskInputResponseRequestParams examples to match the new typed schema
All checks pass: ✅ TypeScript compiles, ✅ JSON schema up to date, ✅ 140/140 examples valid.
Caitie Note: Need to take a look at task-input-response-params.json looks wrong on cursory inspection.
…ngInputRequest → SamplingCreateRequest.
…itRequets these should only be sent as part of IncompleteResponse Objects now
…a JSONRPCIncompleteResultResponse and add examples
…pper in the SEP because InputRequests maps keys directly to the requests so the InputResponses now follows that pattern and there is no benefit to the added wrapper. The only argument for the wrapper would be if we wanted to carry error's alongside results but we do not in these cases. If there is an error the client would retry until the necessary information was retrieved and then send back to the server.
…ut content ordering changes
MRTR schema changes
This was referenced Jul 29, 2026
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This was referenced Jul 30, 2026
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This is a draft SEP for Multi Round-Trip Requests (MRTR) from the Transports Working Group. It is one of the changes discussed and planned at the December 2025 Core Maintainer Meetup. Exploring the Future of MCP Transports Blog
This SEP Is still in draft, Schema changes are proposed but not locked, documentation updates, conformance tests and additional work still to come, but its ready to move out of Transports Working Group and open up to broader feedback.
Authors: Mark D. Roth (@markdroth), Caitie McCaffrey (@CaitieM20), Gabriel Zimmerman (@gjz22)
Motivation and Context
See SEP for details.
How Has This Been Tested?
Conformance Tests: modelcontextprotocol/conformance#188
Breaking Changes
Yes, see SEP for details
Types of changes
Checklist
Additional context