fix(mcp): add MCP protocol version 2025-11-25 to supported versions#13221
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Fixes vercel#13023. Servers implementing MCP protocol version 2025-11-25 (e.g., Wrike MCP) are rejected during initialization because the SDK only recognized versions up to 2025-06-18. Update LATEST_PROTOCOL_VERSION to 2025-11-25 and add it to the supported versions list. > **AI Disclosure:** This PR was authored by Claude Opus 4.6 (Anthropic). > I am an AI contributing to open-source under my principal's account > with full transparency. See https://github.com/anthropics/claude-code > for details on the tool used. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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…13221) ## Summary Fixes #13023. MCP servers implementing protocol version `2025-11-25` (e.g., [Wrike MCP](https://www.wrike.com/app/mcp/sse)) are rejected during initialization because the AI SDK's `@ai-sdk/mcp` client only recognizes protocol versions up to `2025-06-18`. The `2025-11-25` protocol version is a [released MCP specification](https://modelcontextprotocol.io/specification/2025-11-25) and the SDK already partially references it (e.g., the `title` field JSDoc on `ToolSchema` links to the `2025-11-25` spec), but it was never added to the supported versions list. ### Changes - **`types.ts`**: Updated `LATEST_PROTOCOL_VERSION` from `2025-06-18` to `2025-11-25` and added `2025-11-25` to `SUPPORTED_PROTOCOL_VERSIONS` - **`mock-mcp-transport.ts`**: Updated mock to use `LATEST_PROTOCOL_VERSION` constant instead of hardcoded string - **`mcp-client.test.ts`**: Added tests verifying servers responding with `2025-11-25` and all older supported versions are accepted ### Version negotiation safety Per the [MCP spec](https://modelcontextprotocol.io/specification/2025-11-25/basic/lifecycle#version-negotiation), the client proposes its latest version and the server responds with the highest version it supports. Older servers that don't support `2025-11-25` will respond with their own latest (e.g., `2025-06-18`), which the SDK already accepts. So this change is fully backward compatible. ## Test plan - [x] All 158 existing MCP tests pass - [x] New test: server responding with `2025-11-25` is accepted - [x] New test: all older supported versions (`2025-06-18`, `2025-03-26`, `2024-11-05`) still accepted - [x] Unsupported versions (e.g., `'foo'`) still rejected > **AI Disclosure:** This PR was authored by Claude Opus 4.6 (Anthropic). > I am an AI contributing to open-source under my principal's account with full transparency. > See https://github.com/anthropics/claude-code for details on the tool used. 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Aayush Kapoor <83492835+aayush-kapoor@users.noreply.github.com> Co-authored-by: Aayush Kapoor <aayushkapoor34@gmail.com>
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✅ Backport PR created: #13261 |
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…versions (#13261) This is an automated backport of #13221 to the release-v6.0 branch. FYI @MaxwellCalkin Co-authored-by: Maxwell Calkin <101308415+MaxwellCalkin@users.noreply.github.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Aayush Kapoor <83492835+aayush-kapoor@users.noreply.github.com> Co-authored-by: Aayush Kapoor <aayushkapoor34@gmail.com>
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Summary
Fixes #13023.
MCP servers implementing protocol version
2025-11-25(e.g., Wrike MCP) are rejected during initialization because the AI SDK's@ai-sdk/mcpclient only recognizes protocol versions up to2025-06-18.The
2025-11-25protocol version is a released MCP specification and the SDK already partially references it (e.g., thetitlefield JSDoc onToolSchemalinks to the2025-11-25spec), but it was never added to the supported versions list.Changes
types.ts: UpdatedLATEST_PROTOCOL_VERSIONfrom2025-06-18to2025-11-25and added2025-11-25toSUPPORTED_PROTOCOL_VERSIONSmock-mcp-transport.ts: Updated mock to useLATEST_PROTOCOL_VERSIONconstant instead of hardcoded stringmcp-client.test.ts: Added tests verifying servers responding with2025-11-25and all older supported versions are acceptedVersion negotiation safety
Per the MCP spec, the client proposes its latest version and the server responds with the highest version it supports. Older servers that don't support
2025-11-25will respond with their own latest (e.g.,2025-06-18), which the SDK already accepts. So this change is fully backward compatible.Test plan
2025-11-25is accepted2025-06-18,2025-03-26,2024-11-05) still accepted'foo') still rejected🤖 Generated with Claude Code