fix(happy-cli): create per-request MCP transport for SDK >= 1.26.0#688
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davidrimshnick wants to merge 2 commits intoslopus:mainfrom
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fix(happy-cli): create per-request MCP transport for SDK >= 1.26.0#688davidrimshnick wants to merge 2 commits intoslopus:mainfrom
davidrimshnick wants to merge 2 commits intoslopus:mainfrom
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… crash @modelcontextprotocol/sdk 1.26.0 added a guard that throws when a stateless StreamableHTTPServerTransport is reused across requests. The Happy MCP server was creating a single transport at startup and reusing it, causing HTTP 500 on every request after the first. Create a fresh McpServer + transport per request, following the SDK's own simpleStatelessStreamableHttp.ts example. Fixes slopus#634 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Verifies that the Happy MCP server handles multiple sequential requests without returning HTTP 500 — the core regression from @modelcontextprotocol/sdk >= 1.26.0. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
@modelcontextprotocol/sdk@1.26.0(released Feb 4, 2026) added a guard that throws when a statelessStreamableHTTPServerTransportis reused across requestsMcpServer+StreamableHTTPServerTransportper request, following the SDK's ownsimpleStatelessStreamableHttp.tsexampleFixes #634
Test plan
startHappyServer.test.tsthat verify:happy-coderwith@modelcontextprotocol/sdk@1.26.0+, start a session, and verifymcp__happy__change_titleworks on repeated calls🤖 Generated with Claude Code