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@jonathanelmgren jonathanelmgren commented Dec 22, 2025

Summary

Pins @modelcontextprotocol/sdk to ~1.24.0 to avoid breaking changes in 1.25.x that cause 406 errors in the MCP plugin.

Problem

The current dependency declaration ^1.17.2 allows installation of @modelcontextprotocol/sdk@1.25.x, which introduced breaking changes in the WebStandardStreamableHTTPServerTransport that cause the MCP plugin to fail with 406 "Not Acceptable" errors.

Solution

Change the dependency to use ~1.24.0 (tilde) instead of ^1.17.2 (caret), restricting updates to patch versions only (1.24.x).

Changes

  • packages/plugin-mcp/package.json: Update SDK version from ^1.17.2 to ~1.24.0

Breaking Changes

None - this prevents a breaking change from affecting users.

Follow-up

Once the @modelcontextprotocol/sdk team releases a fixed version or documents the correct usage pattern for 1.25.x+, we can update to allow newer versions.

closes: #15016
closes: #14952

@jonathanelmgren jonathanelmgren changed the title fix: pin modelcontextprotocol/sdk dependency version to 1.21.0 fix(plugin-mcp): pin modelcontextprotocol/sdk dependency version to 1.21.0 Dec 22, 2025
@jonathanelmgren jonathanelmgren changed the title fix(plugin-mcp): pin modelcontextprotocol/sdk dependency version to 1.21.0 fix(plugin-mcp): pin modelcontextprotocol/sdk dependency version to 1.24.0 Dec 22, 2025
@DanRibbens DanRibbens enabled auto-merge (squash) December 30, 2025 21:20
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MCP Plugin Incompatible with @modelcontextprotocol/sdk 1.25.x MCP Server not starting

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