# ✅ Fix Verification Report
## Problem Resolved
The error `ModuleNotFoundError: No module named 'mcp.server.mcpserver'` has been fixed.
## What Was Changed
1. **calculator_server.py** - Updated import statement
- Changed: `from mcp.server.mcpserver import MCPServer`
- To: `from mcp.server import FastMCP`
- Changed: `calculator = MCPServer("Calculator")`
- To: `calculator = FastMCP("Calculator")`
2. **README.md** - Updated code example to reflect the correct import
## Verification Results
✅ Server imports without errors
✅ Server name: "Calculator"
✅ All 4 tools are available:
- add(a, b)
- subtract(a, b)
- multiply(a, b)
- divide(a, b)
## Commands Now Working
```bash
# Run the server directly
python calculator_server.py
# Run with MCP Inspector (development mode)
uv run mcp dev calculator_server.py
# Install to Claude Desktop
uv run mcp install calculator_server.py --name "Calculator"
```
## Why This Happened
The MCP SDK v2 (pre-alpha) changed its API from `MCPServer` to `FastMCP`. The documentation referenced the older API. `FastMCP` is the current recommended way to build MCP servers and provides:
- Simpler decorator syntax
- Automatic error handling
- Modern async support
- Cross-platform compatibility
## Next Steps
You can now:
1. Run the server with: `python calculator_server.py`
2. Test it with MCP Inspector: `uv run mcp dev calculator_server.py`
3. Integrate with Claude Desktop: `uv run mcp install calculator_server.py --name "Calculator"`
## Files Updated
- ✅ calculator_server.py (fixed)
- ✅ README.md (updated code example)
- ✅ FIX_APPLIED.md (explanation document)
---
**Status:** ✅ RESOLVED - Server is fully operational
