# MCP SDK Phase 3: Runtime Test Report

**Date**: 2025-11-09
**Test Environment**: Development
**SDK Version**: ModelContextProtocol v0.4.0-preview.3
**Application Port**: http://localhost:5167
**Test Duration**: ~30 minutes

---

## Executive Summary

The Phase 3 runtime testing revealed that the Microsoft MCP SDK **is NOT being used** in the current implementation. Instead, ColaFlow has a **custom MCP Server implementation** that uses HTTP JSON-RPC instead of the SDK's stdio transport.

### Key Findings:

✅ **What Works:**
- Application starts successfully
- Custom MCP endpoint (`/mcp`) is operational
- MCP Resources are registered (6 resources discovered)
- MCP Protocol Handler is initialized with 6 method handlers
- API Key authentication is functional

❌ **What Doesn't Work:**
- Microsoft MCP SDK is registered but not actually used
- No stdio transport (required for Claude Desktop integration)
- SDK's `.WithToolsFromAssembly()` and `.WithResourcesFromAssembly()` don't integrate with custom implementation

---

## 1. Application Startup Analysis

### Startup Logs (Successful)

```log
[2025-11-09 22:37:10.571] [INF] Initializing MCP Resource Registry with auto-discovery...
[2025-11-09 22:37:10.591] [INF] Starting MCP Resource discovery via Assembly scanning...
[2025-11-09 22:37:10.598] [INF] Discovered 6 MCP Resource types
[2025-11-09 22:37:10.709] [INF] Instantiated 6 MCP Resources
[2025-11-09 22:37:10.710] [INF] Registered MCP Resource: colaflow://issues.get/{id} - Issue Details [Issues]
[2025-11-09 22:37:10.710] [INF] Registered MCP Resource: colaflow://issues.search - Issues Search [Issues]
[2025-11-09 22:37:10.711] [INF] Registered MCP Resource: colaflow://projects.get/{id} - Project Details [Projects]
[2025-11-09 22:37:10.711] [INF] Registered MCP Resource: colaflow://projects.list - Projects List [Projects]
[2025-11-09 22:37:10.711] [INF] Registered MCP Resource: colaflow://sprints.current - Current Sprint [Sprints]
[2025-11-09 22:37:10.711] [INF] Registered MCP Resource: colaflow://users.list - Team Members [Users]
[2025-11-09 22:37:10.711] [INF] MCP Resource Registry initialized: 6 resources in 4 categories
```

**Analysis:**
- Application starts successfully
- Custom MCP Resource Registry is initialized (not from SDK)
- 6 MCP Resources discovered via custom assembly scanning
- All database migrations applied successfully
- Application listening on `http://localhost:5167`

---

## 2. Endpoint Discovery Results

### Test Results:

| Endpoint Tested | Method | Result | Status Code | Notes |
|-----------------|--------|--------|-------------|-------|
| `/health` | GET | ✅ Success | 200 | Health check endpoint works |
| `/mcp` | POST | ⚠️ 401 Unauthorized | 401 | Requires API Key authentication |
| `/api/mcp` | POST | ❌ Not Found | 404 | Endpoint does not exist |
| `/.well-known/mcp` | POST | ❌ Not Found | 404 | Endpoint does not exist |
| `/mcp/sse` | POST | ⚠️ 401 Unauthorized | 401 | Requires API Key authentication |
| `/mcp/ws` | POST | ⚠️ 401 Unauthorized | 401 | Requires API Key authentication |

### Key Findings:

1. **MCP Endpoint**: `/mcp` (HTTP JSON-RPC, not stdio)
2. **Authentication**: API Key required (`Authorization: Bearer <api_key>`)
3. **MCP Protocol Handler**: Custom implementation, not from Microsoft SDK
4. **Method Handlers**: 6 handlers registered
   - `initialize`
   - `resources/list`
   - `resources/read`
   - `resources/health`
   - `tools/list`
   - `tools/call`

---

## 3. SDK Integration Analysis

### Code Review Findings:

#### Program.cs (Lines 51-56)
```csharp
// ============================================
// Register Microsoft MCP SDK (PoC - Phase 1)
// ============================================
builder.Services.AddMcpServer()
    .WithToolsFromAssembly()  // Auto-discover tools with [McpServerToolType] attribute
    .WithResourcesFromAssembly(); // Auto-discover resources with [McpServerResourceType] attribute
```

#### Log Evidence (Line 103)
```log
[2025-11-09 22:41:00.442] [INF] MCP Protocol Handler initialized with 6 method handlers:
initialize, resources/list, resources/read, resources/health, tools/list, tools/call
```

### Critical Issue:

The Microsoft MCP SDK is **registered** in DI but **not actually used** at runtime. The "MCP Protocol Handler" mentioned in logs is **ColaFlow's custom implementation**, not the SDK.

**Evidence:**
1. Custom middleware: `McpApiKeyAuthenticationMiddleware` (custom, not SDK)
2. Custom protocol handler mentioned in logs
3. HTTP transport (custom) vs SDK's stdio transport
4. Custom resource registry (not SDK's)

---

## 4. Transport Layer Analysis

### Expected (Microsoft SDK): stdio
- **What it is**: Standard input/output communication
- **Use case**: Claude Desktop, command-line clients
- **Protocol**: MCP JSON-RPC over stdio

### Actual (ColaFlow Custom): HTTP JSON-RPC
- **What it is**: HTTP REST API with JSON-RPC messages
- **Use case**: Web clients, HTTP-based integrations
- **Protocol**: MCP JSON-RPC over HTTP POST
- **Authentication**: Custom API Key via Bearer token

**Conclusion**: The Microsoft MCP SDK's stdio transport is not being used. ColaFlow has built a custom HTTP-based MCP implementation.

---

## 5. SDK PoC Tools Analysis

### SdkPocTools.cs
```csharp
[McpServerToolType]
public class SdkPocTools
{
    private readonly ILogger<SdkPocTools> _logger;

    public SdkPocTools(ILogger<SdkPocTools> logger)
    {
        _logger = logger;
    }

    [McpServerTool("Ping", "Simple ping tool to verify MCP SDK is working")]
    public string Ping()
    {
        return "Pong! MCP SDK is working.";
    }

    [McpServerTool("GetServerTime", "Get current server time in UTC")]
    public string GetServerTime()
    {
        _logger.LogInformation("GetServerTime called via MCP SDK");
        return $"Server time (UTC): {DateTime.UtcNow:yyyy-MM-dd HH:mm:ss}";
    }

    [McpServerTool("GetProjectInfo", "Get basic project information")]
    public string GetProjectInfo(string projectId)
    {
        return $"Project ID: {projectId} (This is a PoC - actual implementation would query database)";
    }
}
```

### Testing Status:

| Tool | Can be Called? | Reason |
|------|----------------|--------|
| `Ping` | ❌ No | SDK not integrated with custom MCP handler |
| `GetServerTime` | ❌ No | SDK not integrated with custom MCP handler |
| `GetProjectInfo` | ❌ No | SDK not integrated with custom MCP handler |

**Why it doesn't work:**
- The SDK's `.WithToolsFromAssembly()` discovers tools with `[McpServerToolType]` attribute
- BUT the custom MCP protocol handler doesn't route to SDK tools
- The custom handler only knows about custom-registered tools

---

## 6. Dependency Injection Verification

### Expected Behavior:
- `SdkPocTools` should be instantiated by DI
- `ILogger<SdkPocTools>` should be injected in constructor
- When `GetServerTime` is called, logger should output: `"GetServerTime called via MCP SDK"`

### Actual Result:
- ❌ **Cannot verify** - SDK tools are not being called because SDK is not integrated with custom handler
- No log entries found for `"GetServerTime called via MCP SDK"`
- DI registration is correct, but tools are never invoked

---

## 7. Error Handling Analysis

### Test: Missing API Key
```http
POST /mcp HTTP/1.1
Content-Type: application/json

{"jsonrpc":"2.0","id":1,"method":"ping"}
```

**Response:**
```json
{
  "jsonrpc": "2.0",
  "error": {
    "code": -32001,
    "message": "Unauthorized",
    "data": {
      "details": "Missing API Key. Please provide Authorization: Bearer <api_key> header."
    }
  }
}
```

**Status**: ✅ Error handling works correctly for authentication failures

---

## 8. Performance Analysis

### Measurements:

| Operation | Duration | Notes |
|-----------|----------|-------|
| Application Startup | ~2 seconds | Includes DB migrations |
| MCP Resource Discovery | ~120ms | Custom assembly scanning |
| Health Check Response | ~50ms | First request (cold start) |
| MCP Endpoint (401) | <1ms | Authentication rejection |

**Conclusion**: Performance is acceptable for custom implementation.

---

## 9. Critical Issues Discovered

### Issue #1: SDK Not Actually Used
**Severity**: 🔴 Critical
**Description**: Microsoft MCP SDK is registered but not integrated with custom MCP handler

**Evidence:**
- SDK registration in Program.cs (lines 54-56)
- Custom MCP handler used at runtime (logs show "MCP Protocol Handler")
- No stdio transport (SDK's default)
- SDK tools never called

**Impact**:
- Cannot test SDK features (stdio transport, tool discovery, resource discovery)
- Phase 1/2/3 testing goals not met
- Need to either: (a) use SDK properly, or (b) remove SDK dependency

### Issue #2: HTTP vs stdio Transport Mismatch
**Severity**: 🟡 Medium
**Description**: SDK expects stdio, but application uses HTTP

**Impact**:
- Cannot integrate with Claude Desktop (requires stdio)
- SDK's built-in features (stdio server, message framing) not utilized

### Issue #3: Tool Discovery Not Working
**Severity**: 🟡 Medium
**Description**: `.WithToolsFromAssembly()` discovers tools but they're not exposed via custom handler

**Impact**:
- SDK PoC tools (Ping, GetServerTime, GetProjectInfo) cannot be tested
- Cannot verify DI injection in tools

---

## 10. Recommendations

### Short-term (Phase 3 Completion):

1. **Decision Required**: Choose one approach:
   - **Option A**: Remove Microsoft SDK, document custom implementation
   - **Option B**: Integrate SDK properly (use stdio transport)
   - **Option C**: Keep both (SDK for Claude Desktop, custom for web)

2. **If keeping SDK (Option B/C)**:
   - Implement stdio transport using SDK's `StdioServer`
   - Bridge SDK tools to custom HTTP handler
   - Add configuration to switch between transports

3. **Documentation**:
   - Update architecture docs to reflect actual implementation
   - Document why custom implementation was chosen over SDK
   - Provide examples for both transports

### Long-term (Production):

1. **Transport Strategy**:
   ```
   Client Type          → Transport
   -----------------------------------
   Claude Desktop       → stdio (SDK)
   Web Clients          → HTTP (custom)
   Mobile Apps          → HTTP (custom)
   CLI Tools            → stdio (SDK)
   ```

2. **Unified Tool Registry**:
   - Create bridge between SDK tools and custom tools
   - Single source of truth for tool definitions
   - Support both `[McpServerTool]` (SDK) and custom attributes

3. **Testing**:
   - Integration tests for SDK tools
   - E2E tests for HTTP MCP endpoint
   - Claude Desktop integration tests (stdio)

---

## 11. Test Artifacts

### Files Created:
- ✅ `scripts/test-mcp-runtime.ps1` - HTTP endpoint discovery script
- ✅ `scripts/create-test-api-key.sql` - SQL script for test API key
- ✅ `scripts/create-test-api-key.ps1` - PowerShell script for API key creation

### Test Results:
- ✅ `scripts/mcp-runtime-test-results.json` - Detailed test results

---

## 12. Answers to Key Questions

### Q1: SDK uses what transport layer?
**A**: SDK is designed for **stdio**, but application uses **custom HTTP** transport

### Q2: Endpoint URL is what?
**A**: `http://localhost:5167/mcp` (custom HTTP endpoint, not SDK)

### Q3: How does SDK register endpoints?
**A**: SDK expects stdio, no HTTP endpoint registration. Custom handler provides HTTP endpoint.

### Q4: Are tools and resources correctly discovered?
**A**:
- **Resources**: ✅ Yes (custom discovery, 6 resources)
- **Tools**: ⚠️ Discovered by SDK but not exposed via custom handler

### Q5: Does DI work at runtime?
**A**: ❌ Cannot verify - SDK tools never called because SDK not integrated

### Q6: Performance?
**A**: ✅ Good (startup: 2s, response: <50ms)

---

## 13. Next Steps

### Immediate Action Required:

1. **Clarify Architecture Decision**:
   - Should we use Microsoft MCP SDK at all?
   - Or document this as "custom MCP implementation"?

2. **If Using SDK**:
   ```
   Phase 3a: Implement stdio transport
   Phase 3b: Bridge SDK tools to custom HTTP handler
   Phase 3c: Test with Claude Desktop
   ```

3. **If Not Using SDK**:
   ```
   Phase 3a: Remove SDK NuGet package
   Phase 3b: Remove SDK registration from Program.cs
   Phase 3c: Document custom MCP implementation
   ```

### Testing Blocked:

❌ **Cannot proceed with Phase 3 testing** because:
- SDK tools cannot be called
- No stdio transport to test
- No integration between SDK and custom handler

**Recommendation**: Make architecture decision before proceeding.

---

## Conclusion

The Microsoft MCP SDK (ModelContextProtocol v0.4.0-preview.3) is **registered but not functional** in the current ColaFlow implementation. The application uses a **custom HTTP-based MCP protocol** instead of the SDK's stdio-based approach.

### Should we use the SDK?

**Pros of SDK:**
- ✅ Standard MCP protocol support
- ✅ stdio transport for Claude Desktop
- ✅ Built-in tool/resource discovery
- ✅ Microsoft-maintained

**Cons of SDK:**
- ❌ stdio only (no HTTP)
- ❌ Requires process management
- ❌ Not suitable for web APIs
- ❌ Preview version (unstable)

**Recommendation**: Keep custom HTTP implementation for web clients, optionally add SDK's stdio transport for Claude Desktop integration. Use a **hybrid approach** where:
- HTTP endpoint serves web/mobile clients (current implementation)
- stdio endpoint serves Claude Desktop (SDK integration)
- Shared tool/resource registry

---

**Report Generated**: 2025-11-09
**Test Status**: Phase 3 Incomplete (awaiting architecture decision)
**Next Phase**: Phase 3a (stdio transport) OR Phase 4 (production implementation)
