fix(mcp): comply with spec on protocol version negotiation#8
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The initialize handler returned JSON-RPC error -32602 for any client protocolVersion that did not exactly equal '2025-03-26'. This violates the MCP spec on version negotiation, which requires the server to respond with a version it does support and let the client decide whether to continue or disconnect. The strict-equality check broke every client newer than 2025-03-26 (e.g. Claude Code now sends '2025-11-25'), forcing users to either pin to an old client or patch the vendor. Fix: drop the rejection branch. The server already responds with kSupportedProtocolVersion in the result; that is the entire contract.
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The initialize handler returned JSON-RPC error -32602 for any client protocolVersion that did not exactly equal '2025-03-26'. This violates the MCP spec on version negotiation, which requires the server to respond with a version it does support and let the client decide whether to continue or disconnect.
The strict-equality check broke every client newer than 2025-03-26 (e.g. Claude Code now sends '2025-11-25'), forcing users to either pin to an old client or patch the vendor.
Fix: drop the rejection branch. The server already responds with kSupportedProtocolVersion in the result; that is the entire contract.