{
    "action": "tool_call",
    "reasoning": "The question asks about duplicate or near-duplicate rows across the dataset. Since this is a multi-table dataset with 51 tables, I need to check for duplicates systematically. I'll start by examining the largest tables for exact duplicates using GROUP BY with all columns and HAVING COUNT(*) > 1. The evidence shows columns_catalog is the largest table (74.6% of rows), so I'll begin there. First, I need to see its columns to write the duplicate-detection query.",
    "tool": "inspect_columns",
    "args": {
        "table": "columns_catalog"
    }
}