Upgrade to MCP go-sdk v1.0.0

Summary

This PR upgrades the Model Context Protocol (MCP) SDK from v0.5.0 to v1.0.0, the first stable release of the go-sdk. This update ensures long-term stability and compatibility with the MCP specification.

Changes

SDK Upgrade

• ✅ Updated github.com/modelcontextprotocol/go-sdk from v0.5.0 to v1.0.0
• ✅ Fixed breaking API change in NewSSEHandler which now requires &mcp.SSEOptions{} parameter
• ✅ Cleaned up dependencies with go mod tidy

Test Fixes

• ✅ Updated integration tests to handle JSON-formatted output from yardstick-client
• ✅ Fixed endpoint tests to properly handle MCP-compliant HTTP status codes:
  • GET requests without session return 405 (Method Not Allowed) as per spec
  • Added proper Accept: text/event-stream header for SSE endpoints
• ✅ Improved error handling and output capture in test scripts

Documentation

• ✅ Added comprehensive CLAUDE.md documentation for AI agent context
• ✅ Updated dependency versions in documentation
• ✅ Added details about testing infrastructure and integration points

Testing

• ✅ All unit tests passing: go test ./...
• ✅ All integration tests passing: task test-integration
• ✅ Build successful: go build ./...
• ✅ Container image builds successfully with ko

MCP SDK v1.0.0 Benefits

• Stable API: No breaking changes promised going forward
• Full Spec Compliance: Complete implementation of MCP specification 2025-06-18
• Bug Fixes: 60 out of 61 reported bugs resolved
• Better Session Management: Improved handling of stateful/stateless modes
• Enhanced Transport Support: Refined StreamableHTTP and SSE implementations

Compatibility

This upgrade maintains full backward compatibility with existing MCP clients while ensuring compliance with the latest protocol specification.

Related Links

• MCP SDK v1.0.0 Release
• MCP Specification

This PR was developed with assistance from Claude to ensure thorough testing and documentation of all changes.