MCP Debugger

# Proxy Timeout Regression Analysis Report ## Executive Summary The "Proxy initialization timed out" error is **CONFIRMED** to be caused by the uncommitted JavaScript adapter work. The regression is not present in the clean main branch code but appears when the JavaScript adapter changes are included. ## Test Results ### Testing Sequence 1. **With JavaScript Changes (Initial Test)** - Result: FAILED with "Proxy initialization timed out" 2. **Clean Repository (Main Branch)** - Initial test failed due to stale server connection - After MCP Server Restart: **SUCCESS** - Debugging works correctly - Behavior matches NPX version exactly 3. **With JavaScript Changes (After Rebuild)** - Result: FAILED with "Proxy initialization timed out" - Confirms JavaScript adapter changes are causing the issue ### Root Cause The proxy timeout is caused by: - Uncommitted JavaScript adapter implementation - Likely integration issues between JavaScript adapter and existing proxy infrastructure - The regression occurs consistently when JavaScript adapter code is present ## Key Findings 1. **Code Regression Confirmed**: The JavaScript adapter changes are causing the proxy timeout 2. **Clean Repository Works**: The main branch code without JavaScript changes functions correctly 3. **Consistent Failure Pattern**: The proxy timeout occurs every time JavaScript adapter code is included 4. **Server Restart Important**: Testing revealed the importance of restarting MCP servers after builds ## Comparison with NPX Version The clean repository (after server restart) behaves identically to the NPX version: - Same initial pause behavior at line 2 - Same breakpoint functionality - Same variable inspection capabilities ## Recommendations ### Immediate Actions 1. **Isolate JavaScript Adapter Work**: Create a feature branch to isolate JavaScript adapter development 2. **Restore Python Functionality**: Work from main branch for Python debugging tasks 3. **Debug Integration Issues**: Investigate why JavaScript adapter is affecting proxy initialization ### Options for Moving Forward 1. **Feature Branch Approach** - Move JavaScript adapter work to `feature/javascript-adapter` branch - Continue development there without affecting main functionality - Merge only when proxy issues are resolved 2. **Temporary Disable JavaScript Adapter** - Comment out JavaScript adapter registration in the adapter factory - This would restore Python functionality while keeping the code 3. **Fix Integration Issues** - Debug why JavaScript adapter initialization is timing out - May involve proxy configuration changes or adapter loading sequence ### Process Improvements 1. **Build Script Enhancement**: Add a post-build message reminding developers to restart MCP servers 2. **Testing Protocol**: Always restart MCP servers as part of testing workflow 3. **Feature Toggle**: Consider adding configuration to enable/disable specific adapters ## Lessons Learned 1. **Server State Management**: MCP server connections must be restarted after builds 2. **Integration Testing**: New adapter implementations can affect core proxy functionality 3. **Isolation Strategy**: Major features should be developed in feature branches ## Uncommitted Files Reference For completeness, here are the uncommitted files related to JavaScript adapter: - `src/adapters/javascript/index.ts` - `src/adapters/javascript/javascript-adapter-factory.ts` - `src/adapters/javascript/javascript-adapter.ts` - `tests/core/integration/javascript-debugging.test.ts` - `scripts/download-js-debug.cjs` - `run-js-debug-test.js` Modified proxy-related files: - `src/proxy/dap-proxy-connection-manager.ts` - `src/proxy/dap-proxy-interfaces.ts` - `src/proxy/dap-proxy-worker.ts` - `src/proxy/proxy-config.ts` - `src/proxy/proxy-manager.ts` ## Conclusion The proxy timeout issue is confirmed to be caused by the JavaScript adapter implementation. The regression is real and affects all debugging functionality when the JavaScript adapter code is present. The recommended approach is to isolate this work in a feature branch until the integration issues are resolved. Python debugging functionality works perfectly in the clean main branch. Key takeaways: 1. JavaScript adapter integration is causing proxy initialization timeouts 2. Always restart MCP server connections after builds for accurate testing 3. Feature branches are essential for isolating potentially breaking changes