refactor: upgrade MCP client to SDK v2 packages - #449
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chore: promote dev to main (open-issues-batch + security fixes)
docs: add v1.0.33 release notes
This was referenced Aug 25, 2026
…tiation - swap @modelcontextprotocol/sdk@1.29.0 for @modelcontextprotocol/client@2.0.0 (+core, server dev-only); workspace zod ^4.2.0; drop stale v1 patch - remove StreamableHTTP->SSE fallback; Streamable HTTP failure is terminal - handler registration moved to method strings; oauth-provider types from client root; test mocks re-pointed to the v2 package root - ConfigMCPV1 local/remote gain optional protocol: auto|legacy|modern, mapped to ClientOptions.versionNegotiation (default auto probes server/discover with 2025 fallback; modern pins 2026-07-28) - regenerate JS SDK types; mcp auth diagnostics mirror the era mapping - behavior note: v2 removes transparent 404 session recovery and SSE-only (pre-2025-03-26) servers no longer connect; protocol: legacy is the escape hatch Closes#447Closes#448
LeXwDeX
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August 25, 2026 14:04
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Closes#447
Closes#448
Why
The MCP ecosystem moved: the
2026-07-28specification is stateless (noinitializehandshake, noMcp-Session-Id,server/discoverera probing), and the TypeScript SDK v2 (@modelcontextprotocol/client@2.0.0) implements it with built-in era negotiation and automatic fallback. We were pinned to@modelcontextprotocol/sdk@1.29.0(v1, maintenance-only). Rather than building a v1↔v2 bridge process, the SDK'sversionNegotiationcovers both worlds: one v2 code path, legacy servers transparently supported.What changed
#447 — SDK v2 migration (behavior-preserving)
@modelcontextprotocol/sdk→@modelcontextprotocol/client@2.0.0+core@2.0.0(serverdev-only for tests); workspace zod^4.2.0; stale v1 patch entry and patch file removedconnectRemote— Streamable HTTP failure is terminalroots/list,elicitation/create,notifications/message,notifications/tools/list_changed);callToolschema-arg drop; test mocks re-pointed to the v2 package root#448 — configurable 2026-07-28 era negotiation
ConfigMCPV1local/remote entries gain optionalprotocol: "auto" | "legacy" | "modern"(defaultauto); JS SDK types regeneratedcreateClientmaps it toClientOptions.versionNegotiation:autoprobesserver/discoverwith conservative fallback to the 2025 handshake;legacyskips the probe;modernpins2026-07-28with no fallbackmcp authdiagnostics mirror the same mapping; elicitation handler verified compatible with 2026-erainput_requiredauto-fulfilment (no code change needed)Evidence
bun typecheck(packages/opencode): exit 0; root turbo typecheck 29/29bun test test/mcp: 92/92 pass (83 migrated + 9 new inprotocol.test.tscovering parsing + versionNegotiation mapping)bun run lint: 4814 / 4850 warnings (pre-change baseline 4833 → zero new; budget not weakened)test:httpapi: 230 pass / 0 fail / 0 missing; SDKcheck:generateddiff is exactly the+2 protocol?linesdag_fe5fc6f72541xbogE0yDEGwLXU: explore → migrate → era → verify (PASS) → review (PASS, 0 blocking / 7 informational, all informational items addressed in aa3fda5)Behavior notes (for release notes)
protocol: "legacy"does not help there; such servers must upgrade to Streamable HTTPSdkHttpError(CLIENT_HTTP_NOT_IMPLEMENTED, status 404) instead of silently re-initializing;session-recovery.test.tsdocuments the new contractconfig_assistantGo JSON schema embed has no freshness gate