{
    "action": "tool_call",
    "reasoning": "No evidence is available in this turn, so I can't cite earlier results. I'll pull the per-species aggregates from the gold table to ground the petal vs sepal comparison.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT * FROM iris_by_species",
        "purpose": "Compare per-species averages, min, max and median of all four measures to judge which separates the species best",
        "source": "gold"
    }
}