{
    "action": "tool_call",
    "reasoning": "Gold table iris_by_species has per-species aggregates; use it to ground which questions are actually interesting (separation between species).",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT * FROM iris_by_species",
        "purpose": "Per-species averages/min/max to see how well features separate species",
        "source": "gold"
    }
}