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MCP TypeScript SDK 2.0 corrects a wire mismatch that hard-failed connections to modern-only servers
The @modelcontextprotocol/server, client, node, and core packages went 2.0.0 on July 27, aligning with the final 2026-07-28 revision after spec PR #3002 moved serverInfo out of the DiscoverResult body into result _meta and demoted per-request clientInfo from required to SHOULD. Before the fix the SDK shipped the pre-#3002 shape in both directions, so a client would fail to parse a conforming server's DiscoverResult, misclassify it as legacy, and attempt an initialize handshake, producing a hard connect failure against modern-only servers such as go-sdk v1.7.0-pre.3. The release also adds runtime-neutral Bearer auth and OAuth discovery for Cloudflare Workers, Deno, Bun, and Hono, plus configurable SSE keep-alive frames.
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