Data flow
CSV files
On your computer
SQL query
Local, in-process
AI assistant
Receives results only
Raw rows never leave your machine. The model receives the query output, not the dataset.
Your CSV files are never uploaded to Claude or ChatGPT. The AI only receives query results — aggregate data, counts, or filtered rows you explicitly request.
What the AI sees
- The table schemas (column names and types) so it can write valid SQL.
- The output of queries it runs — typically a few rows or aggregates.
- Sensitive columns you've marked (see Hashing) appear as opaque hashes.
ngrok security
The tunnel is end-to-end TLS encrypted between ChatGPT and your machine. ngrok relays bytes but cannot decrypt them. We recommend a reserved domain plus ngrok's basic-auth option for shared environments.