MCP-vs-REST.md•3.61 kB
# MCP HTTP Server: The Correct Implementation
## The Question You Asked
> "so is this as MCP 'HTTP Streamable' was intended? it looks like its just a REST API now?"
**You were absolutely right to question this!** What I initially built was indeed just a REST API, not a true MCP HTTP server.
## What I Built First (REST API)
```typescript
// REST API - Custom endpoints
app.post('/api/search-highlights', async (req, res) => {
const { vector_search_term, full_text_queries } = req.body;
// Custom logic...
res.json({ results: [...] });
});
```
**Problems:**
- ❌ Not MCP-compliant
- ❌ Custom API design
- ❌ Not interoperable with MCP clients
- ❌ Doesn't follow MCP specification
## What MCP HTTP Should Actually Be
```typescript
// MCP HTTP - JSON-RPC 2.0 over HTTP
app.post('/mcp', async (req, res) => {
const { jsonrpc, id, method, params } = req.body;
if (method === 'tools/call') {
const { name, arguments: args } = params;
// Handle MCP tool calls...
res.json({
jsonrpc: "2.0",
id,
result: { content: [...] }
});
}
});
```
**Benefits:**
- ✅ **True MCP protocol over HTTP**
- ✅ JSON-RPC 2.0 compliant
- ✅ Compatible with MCP clients
- ✅ Follows MCP specification
- ✅ **This is what "MCP HTTP Streamable" actually means**
## Key Features
| Aspect | MCP HTTP |
|--------|----------|
| **Protocol** | JSON-RPC 2.0 |
| **Request Format** | MCP standard format |
| **Response Format** | MCP standard format |
| **Tool Calling** | `tools/call` method |
| **Initialization** | `initialize` method |
| **Tool Discovery** | `tools/list` method |
| **Client Compatibility** | Any MCP client |
| **Streaming** | MCP streaming spec |
| **Debugging** | Comprehensive logging |
## MCP HTTP Request Example
```json
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "search_readwise_highlights",
"arguments": {
"vector_search_term": "machine learning"
}
}
}
```
## MCP HTTP Response Example
```json
{
"jsonrpc": "2.0",
"id": 1,
"result": {
"content": [
{
"type": "text",
"text": "[...search results...]"
}
]
}
}
```
## Why This Matters
1. **Interoperability**: MCP HTTP servers can work with any MCP client
2. **Standards Compliance**: Follows the official MCP specification
3. **Tool Discovery**: Clients can discover available tools automatically
4. **Error Handling**: Standardized error codes and formats
5. **Streaming**: Proper MCP streaming implementation
6. **Debugging**: Comprehensive logging for development and troubleshooting
## Network Connectivity
The server binds to all network interfaces (`0.0.0.0`), making it accessible from:
- **Localhost**: `http://localhost:3000`
- **Local Network**: `http://YOUR_IP_ADDRESS:3000`
- **Docker**: `http://host.docker.internal:3000`
This allows other devices on your network to connect to the server.
## Debugging Features
The server includes comprehensive debugging capabilities:
- **Connection tracking**: Every incoming request with IP and user agent
- **Request processing**: Step-by-step MCP request handling
- **Tool execution**: Detailed tool call processing
- **API interactions**: Readwise API calls and responses
- **Streaming**: Real-time streaming progress
- **Error details**: Full error stack traces and context
## Conclusion
The **MCP HTTP Server** (`src/mcp-http-server.ts`) is the correct implementation for "MCP HTTP Streamable". It provides true MCP protocol over HTTP with comprehensive debugging capabilities.
**This is the proper MCP HTTP implementation!** 🎯