{
    "action": "tool_call",
    "reasoning": "I've found several data quality patterns so far: (1) sales_pipeline has logical null patterns tied to deal_stage, (2) close_value ranges align well with product sales_price, (3) accounts revenue/employees have no negatives or impossible years. Now I need to check for: (a) referential integrity - do all sales_pipeline.product values exist in products table? do all sales_agent values exist in sales_teams? (b) accounts sector/subsidiary_of consistency, (c) any text format issues in key fields. Let me check referential integrity first.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT 'pipeline_products_not_in_products' AS issue, COUNT(*) AS count FROM raw.sales_pipeline sp WHERE sp.product NOT IN (SELECT product FROM raw.products) UNION ALL SELECT 'pipeline_agents_not_in_teams', COUNT(*) FROM raw.sales_pipeline sp WHERE sp.sales_agent NOT IN (SELECT sales_agent FROM raw.sales_teams) UNION ALL SELECT 'pipeline_accounts_not_in_accounts', COUNT(*) FROM raw.sales_pipeline sp WHERE sp.account NOT IN (SELECT account FROM raw.accounts)",
        "purpose": "Check referential integrity - whether sales_pipeline references to products, sales_teams, and accounts tables are valid"
    }
}