Fix MCP HTTP protocol fallback race - #1861
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Aaronontheweb
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August 10, 2026 22:03
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| ? Assert.Single(versions) | ||
| : null, | ||
| request.Headers.Authorization?.ToString()); | ||
| return Task.FromResult(new HttpResponseMessage(HttpStatusCode.Accepted)); |
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Summary
initializerequestsCause
MCP SDK 2.0 can complete a
2026-07-28discovery response at the same time that its five-second probe wait is cancelled. The client then starts a2025-11-25initialize fallback, but the HTTP transport can keep the earlier version and attach it as a header. A conforming server rejects that mixed request.Validation
dotnet build Netclaw.slnx -c Release --no-restoredotnet test Netclaw.slnx -c Release --no-build --no-restoredotnet slopwatch analyze --fail-on warningpwsh ./scripts/Add-FileHeaders.ps1 -Verifyopenspec validate --all --strictdotnet format --verify-no-changesBehavioral evals do not apply because this change does not alter prompts, tools, or model behavior.