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'@modelcontextprotocol/sdk': patch
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`StreamableHTTPServerTransport` and `WebStandardStreamableHTTPServerTransport` now write SSE keep-alive comment frames (`: keepalive`) to open SSE streams so idle connections (e.g. the standalone GET stream, or a POST stream during a long-running tool call) are not killed by
intermediaries or server idle timeouts. Configurable via the new `keepAliveMs` option (default 15000; set 0 to disable).