expense-tracker-mcp2/
├── mcp/
│   ├── server.py            # FastMCP server & tool registration
│   └── tools/
│       └── expense_tools.py # Raw tool functions (called by server)
│
├── services/
│   └── expense_service.py   # Business logic layer
│
├── database/
│   ├── connection.py        # SQLAlchemy engine & session
│   └── models.py            # ORM models
│
├── schemas/
│   └── expense_schema.py    # Pydantic request/response schemas
│
├── .env                     # Environment variables
├── requirements.txt
└── README.md

cd expense-tracker-mcp2
pip install -r requirements.txt

DATABASE_URL=sqlite:///./expenses.db

python mcp/server.py

# Add an expense
tool_add_expense(title="Lunch", amount=250.0, category="Food", date="2026-05-24")

# List this month's expenses
tool_list_expenses(start_date="2026-05-01", end_date="2026-05-31")

# Summarize by category
tool_summarize_expenses(start_date="2026-05-01", end_date="2026-05-31")

{
  "mcpServers": {
    "expense-tracker": {
      "command": "python",
      "args": ["/path/to/expense-tracker-mcp2/mcp/server.py"]
    }
  }
}