{
    "action": "tool_call",
    "reasoning": "I need to compute null counts and percentages for all columns in the adsl table. The previous attempt had a syntax error. I'll query the analytics.column_overview metadata which already contains null_count for each column, then calculate the percentage based on the total 306 rows in adsl.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT column_name, null_count, (null_count * 100.0 / 306) as null_percentage FROM analytics.column_overview WHERE table_name = 'adsl' AND null_count > 0 ORDER BY null_count DESC",
        "purpose": "Find all columns in adsl with missing values and calculate their null percentages",
        "source": "raw"
    }
}