Mar 4, 2026

Why Your LLM Shouldn't Query Your Warehouse Directly

Give an agent a live connection to your warehouse and one of two things happens. Either it gets too much — raw PII, an accidental full-table scan, a query that costs real money — or it gets too little, because it's guessing at table and column names from whatever fragments of schema made it into its context window. Neither failure shows up as an error. It shows up as a confidently wrong answer.

The fix isn't more prompt engineering. It's a layer in between: something that watches the warehouse, keeps a real-time, versioned copy of what the schema actually looks like right now, and hands the agent structured, business-annotated context instead of raw table access. The agent never runs DDL discovery queries against production. It reads from the context layer. The context layer reads from the warehouse on a tight, scheduled poll, and nothing else does.

This is a boring, unglamorous piece of infrastructure right up until the day it isn't — the day an agent almost drops a column that got renamed six minutes ago, and the context layer already knew.