{
    "action": "tool_call",
    "reasoning": "To present the columns, their data types, and their meanings as a rendered table, I will query the analytics.column_overview metadata table.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT column_name, phys_type AS data_type, semantic_role AS meaning FROM analytics.column_overview WHERE table_name = 'iris'",
        "purpose": "Retrieve column names, data types, and meanings for the iris table.",
        "source": "raw"
    }
}