chore: Upgrade @modelcontextprotocol/sdk to ^1.25.3 #759
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This upgrades the MCP SDK from ^1.21.0 to ^1.25.3, bringing in the latest spec compliance fixes and improvements. Part of investigation into #756 - the diagnostic logging from PR #758 will help identify if any issues arise from this upgrade. Note: The agents package remains at 0.2.23 to avoid requiring the AI SDK v6 upgrade that agents 0.3.x requires. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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## Summary Reverts #759 to restore MCP server functionality. ## Problem The MCP SDK upgrade caused a **protocol version mismatch**: - Claude Code sends: `MCP-Protocol-Version: 2025-11-25` - Our server (via `agents@0.2.23`) only supports: `2025-03-26, 2025-06-18` The SDK upgrade alone doesn't help because protocol version support comes from the `agents` package, not the MCP SDK. ## Root Cause Supporting protocol `2025-11-25` requires: - `agents@0.3.5+` (uses MCP SDK 1.25.2 with the newer protocol) - `ai@6.x` (required by agents 0.3.x) - This is a significant migration with breaking changes ## Next Steps - AI SDK 6 migration tracked separately in #756 - This revert restores service for users on older Claude Code versions Fixes #756 🤖 Generated with [Claude Code](https://claude.com/claude-code)
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Summary
@modelcontextprotocol/sdkfrom^1.21.0to^1.25.3Changes
This is a minimal upgrade that only bumps the MCP SDK version. The
agentspackage remains at0.2.23to avoid requiring the AI SDK v6 upgrade thatagents0.3.x requires.Key SDK changes (1.21.0 → 1.25.3)
Notable changes from the changelog:
Risk Assessment
grantedSkillsTest plan
Closes #756
🤖 Generated with Claude Code