{"success":true,"message":"Expense Tracker OpenSearch API","version":"1.0.0","endpoints":{"health":"/health","expenses":"/api/expenses","config":"/api/config","stats":"/api/stats"},"documentation":{"GET /api/expenses":"Get all expenses","GET /api/expenses/month/:month":"Get expenses by month (YYYY-MM)","GET /api/expenses/category/:category":"Get expenses by category","GET /api/expenses/range?startDate=YYYY-MM-DD&endDate=YYYY-MM-DD":"Get expenses by date range","POST /api/expenses":"Create new expense","POST /api/expenses/bulk":"Create multiple expenses","PUT /api/expenses/:id":"Update expense","DELETE /api/expenses/:id":"Delete expense","GET /api/config":"Get configuration","PUT /api/config":"Update configuration","GET /api/stats":"Get expense statistics"}}