AI Privacy Gateway: Strip PII from AI Prompts Before They Leave Your Machine

AI Privacy Gateway

A practical guide to keeping your sensitive data out of AI prompts.

Why it matters

Every prompt you send to a cloud LLM contains potentially sensitive information. A privacy gateway sits between you and the model, stripping PII before anything leaves your machine.

How it works

1. Intercept — the gateway captures outgoing prompts
2. Detect — PII detectors identify emails, phones, addresses, keys
3. Redact — sensitive tokens are replaced with placeholders
4. Forward — the sanitized prompt goes to the model
5. Restore — the response is rehydrated with original values

Key benefits

• Local-first — processing happens on your device
• Zero-knowledge — providers never see your data
• Drop-in — works with any OpenAI-compatible endpoint

Try it

The full implementation is available as an open-source project with a CLI, a local gateway daemon, and MCP integration for AI agents.