fix(mcp): support MCP SDK 1.27+ by creating per-request transport#149
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jungdaesuh wants to merge 1 commit intoCaviraOSS:mainfrom
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fix(mcp): support MCP SDK 1.27+ by creating per-request transport#149jungdaesuh wants to merge 1 commit intoCaviraOSS:mainfrom
jungdaesuh wants to merge 1 commit intoCaviraOSS:mainfrom
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MCP SDK 1.27 introduced a guard that rejects re-initialization on a single StreamableHTTPServerTransport instance. The previous code shared one transport for all connections, which caused every client after the first to receive a 500 error. This broke Claude Code, Codex, and any other MCP client that connects to the server. Changes: - Upgrade @modelcontextprotocol/sdk from 1.22.0 to 1.27.1 - Create a fresh transport + server per request in mcp.ts (stateless mode requires no session state, so this is safe) - Align mcp_tools.ts zod import to "zod/v3" to match zod-to-json-schema's expected type universe, fixing TS2589 caused by the SDK upgrade Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
@modelcontextprotocol/sdkfrom 1.22.0 to 1.27.1 to support MCP protocol version2025-11-25(required by Claude Code 2.1.74+)mcp.ts: MCP SDK 1.27 rejects re-initialization on a singleStreamableHTTPServerTransportinstance ("Invalid Request: Server already initialized"). The previous code shared one transport for all connections, so only the first client could connect — every subsequentinitializerequest returned HTTP 500. Fixed by creating a fresh transport + server per request (safe in stateless mode withsessionIdGenerator: undefined).mcp_tools.ts: The SDK upgrade pulls in zod 3.25+ types that causeType instantiation is excessively deep and possibly infinitewhenzodToJsonSchemareceivesz.ZodType<any>from"zod". Fixed by importing from"zod/v3"to align withzod-to-json-schema's expected type universe.Test plan
tsc --noEmitpasses clean (no TS2589, no errors)initializerequests (verified 3 sequential clients all get 200 OK)StreamableHTTPClientTransport) connects and lists all 6 tools2025-11-25(compatible with Claude Code 2.1.74+)🤖 Generated with Claude Code