{
    "action": "tool_call",
    "reasoning": "No question was stated beyond a prior column-listing attempt; I'll retrieve column metadata to orient and describe the dataset's columns.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT column_name, phys_type, semantic_role, rough_kind, null_count, distinct_count, min_value, max_value, measure_unit FROM analytics.column_overview WHERE table_name = 'bedtime_screentime_sleep_debt'",
        "purpose": "List all columns with types, roles, and ranges to describe their meaning",
        "source": "raw"
    }
}