fix: create MCP server per request (SDK v1.26+ compat)#694
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sparrowfm wants to merge 1 commit intoslopus:mainfrom
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fix: create MCP server per request (SDK v1.26+ compat)#694sparrowfm wants to merge 1 commit intoslopus:mainfrom
sparrowfm wants to merge 1 commit intoslopus:mainfrom
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@modelcontextprotocol/sdk v1.26+ throws "Already connected to a transport" when connect() is called on an McpServer that already has a transport attached. The previous code created a single McpServer + StreamableHTTPServerTransport at startup and reused it for every HTTP request, which broke all MCP tool calls after the first one. Use the stateless per-request factory pattern from the SDK's own simpleStatelessStreamableHttp.ts example: create a fresh McpServer and transport for each incoming request, and clean them up on connection close. Fixes slopus#634 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
change_title) failing on every call after the firstinitializehandshakesimpleStatelessStreamableHttp.tsexampleMcpServer+StreamableHTTPServerTransportper HTTP request and cleans up on connection closeRoot cause
@modelcontextprotocol/sdkv1.26+ throws"Already connected to a transport"ifProtocol.connect()is called when_transportis already set. The previous code created a singleMcpServerandStreamableHTTPServerTransportat startup and reused them for all requests, breaking after the first one.Test plan
change_titleMCP tool works on the first message"Already connected to a transport"or"Server already initialized"errors in logsFixes #634
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