{
    "action": "tool_call",
    "reasoning": "I need to find the time period covered by the dataset. I will query the analytics.column_overview to find the minimum and maximum values of temporal columns across the dataset.",
    "tool": "query_sql",
    "args": {
        "purpose": "Find the overall time period covered by the dataset by looking at temporal columns.",
        "source": "raw",
        "sql": "SELECT table_name, column_name, min_value, max_value FROM analytics.column_overview WHERE rough_kind = 'temporal' OR phys_type IN ('TIMESTAMP', 'DATE') ORDER BY min_value ASC LIMIT 10;"
    }
}