# MCP Logging Research Findings
## Summary of Research on @modelcontextprotocol/sdk@latest Logging API
This document summarizes the research conducted on implementing MCP SDK logging in the file-context-server.
### Key Findings
#### 1. MCP SDK Version
- Current project uses: `@modelcontextprotocol/sdk@1.15.0` (latest)
- SDK includes full logging API support with client-server communication
#### 2. Logging API Structure
```typescript
// Server method available
server.sendLoggingMessage({
level: LoggingLevel, // 8 levels: debug, info, notice, warning, error, critical, alert, emergency
logger?: string, // Optional logger name
data: unknown // Any JSON serializable content
});
// Client control via logging/setLevel requests
// Real-time streaming to MCP clients
```
#### 3. Current State Analysis
- **43+ console.error statements** across 5 files
- **No structured logging** or client visibility
- **stderr output only** - invisible to MCP clients
- **No log level control** or filtering
#### 4. Implementation Architecture Designed
- **LoggingService class** with level filtering and context enrichment
- **Server integration** for client logging/setLevel requests
- **Service injection pattern** for all existing services
- **Performance timing** and structured error context
- **Graceful fallback** to console logging for development
### Documentation Created
1. **[MCP Logging Implementation Brief](./mcp-logging-implementation-brief.md)** (11.3KB)
- Complete project brief with timeline, risks, and success criteria
- Detailed phase-by-phase implementation plan
- Configuration design and testing strategy
2. **[MCP Logging Implementation Summary](./mcp-logging-implementation-summary.md)** (6.6KB)
- Quick reference guide for developers
- File-by-file migration plan with priorities
- Key implementation points and validation steps
3. **[LoggingService Technical Specification](./logging-service-technical-spec.md)** (11.3KB)
- Complete TypeScript interface definitions
- Implementation details with code examples
- Integration patterns and error handling strategy
### Key Implementation Points
#### Migration Strategy
- **Gradual replacement** of 43+ console.error calls
- **Enhanced context** with operation details, file paths, timing
- **Level filtering** based on client preferences
- **Backwards compatibility** maintained throughout
#### Technical Benefits
- **Real-time visibility** for MCP clients
- **Structured debugging** with rich context
- **Performance monitoring** with operation timing
- **Client-controlled verbosity** via log levels
#### Files Requiring Migration
| File | Console Calls | Priority | Context |
|------|---------------|----------|---------|
| `src/index.ts` | 17 | High | Tool operations, file paths |
| `src/services/ProfileService.ts` | 13 | Medium | Profile management |
| `src/services/FileWatcherService.ts` | 9 | Medium | File system events |
| `src/services/CodeAnalysisService.ts` | 2 | Low | Analysis operations |
| `src/services/TemplateService.ts` | 2 | Low | Template rendering |
### Next Steps
The research is complete and ready for implementation. The project brief provides:
1. ✅ **Complete understanding** of MCP SDK logging capabilities
2. ✅ **Detailed implementation plan** with timelines and priorities
3. ✅ **Technical specifications** for all required components
4. ✅ **Migration strategy** for 43+ existing log statements
5. ✅ **Testing approach** and success criteria
6. ✅ **Risk assessment** and mitigation strategies
### Implementation Timeline
- **Week 1**: LoggingService foundation and testing
- **Week 2**: Server integration and client communication
- **Week 3-4**: Service migration and context enhancement
- **Final**: Documentation, testing, and performance validation
This research provides everything needed to implement professional, structured logging that enhances debugging capabilities while maintaining full backwards compatibility.