{
    "action": "tool_call",
    "reasoning": "I have the column metadata from step-0 showing null counts for all 16 columns. Now I need to calculate the percentage of missing values for each column. I'll write a SQL query to compute this, using the total row count (891) and the null counts I can derive from the data.",
    "tool": "query_sql",
    "sql": "SELECT 'Age' AS column_name, COUNT(*) - COUNT(Age) AS missing_count, ROUND(100.0 * (COUNT(*) - COUNT(Age)) / COUNT(*), 2) AS missing_percentage FROM raw.titanic UNION ALL SELECT 'Sex', COUNT(*) - COUNT(Sex), ROUND(100.0 * (COUNT(*) - COUNT(Sex)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Fare', COUNT(*) - COUNT(Fare), ROUND(100.0 * (COUNT(*) - COUNT(Fare)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Name', COUNT(*) - COUNT(Name), ROUND(100.0 * (COUNT(*) - COUNT(Name)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Cabin', COUNT(*) - COUNT(Cabin), ROUND(100.0 * (COUNT(*) - COUNT(Cabin)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Parch', COUNT(*) - COUNT(Parch), ROUND(100.0 * (COUNT(*) - COUNT(Parch)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'SibSp', COUNT(*) - COUNT(SibSp), ROUND(100.0 * (COUNT(*) - COUNT(SibSp)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Pclass', COUNT(*) - COUNT(Pclass), ROUND(100.0 * (COUNT(*) - COUNT(Pclass)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Ticket', COUNT(*) - COUNT(Ticket), ROUND(100.0 * (COUNT(*) - COUNT(Ticket)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Embarked', COUNT(*) - COUNT(Embarked), ROUND(100.0 * (COUNT(*) - COUNT(Embarked)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'Survived', COUNT(*) - COUNT(Survived), ROUND(100.0 * (COUNT(*) - COUNT(Survived)) / COUNT(*), 2) FROM raw.titanic UNION ALL SELECT 'PassengerId', COUNT(*) - COUNT(PassengerId), ROUND(100.0 * (COUNT(*) - COUNT(PassengerId)) / COUNT(*), 2) FROM raw.titanic ORDER BY missing_count DESC",
    "purpose": "Calculate the count and percentage of missing values for each column in the titanic dataset",
    "source": "raw"
}