If a data agent returns €18.6M, production observability should tell you exactly how that answer was constructed. Most Text-to-SQL pipelines log prompts, generated SQL, latency, tokens, and execution status. Those signals matter, but when a business user says, “This number is wrong,” they are not enough. The failure may have happened before SQL generation: "Revenue" → wrong metric "Germany" → wrong dimension Customer data → wrong relationship path "Last quarter" → wrong...