A firewall for AI prompts. Names, contact details, TFNs and secrets are found and masked in this browser, before any model sees the request. The real values are put back in the answer.
Detection on this deviceModel connecting…
ReadyPick an example and send it through the gateway.
On this device
What you typed
Sensitive values highlighted where they were found
Nothing sent yet.
Leaves the device
What the model saw
Real values replaced with placeholders
Nothing sent yet.
Back on this device
What you got back
The model's answer with real values restored
Nothing sent yet.
Raw reply from the model (still masked)
John Smith found on this device<PERSON_1> placeholder the model seesJohn Smith restored after the model answers
Findings
What the detectors caught in this request
Type
Value
Rule
Action
Send a request to see findings.
Audit log
What happened and why. Never the sensitive values themselves.
Time
Verdict
Route
Data types
Rules
ms
How the gateway works
DetectPattern rules with checksums for Australian TFN, Medicare and ABN numbers, card numbers (Luhn), emails, AU phone numbers and IPs, plus name and company heuristics and secret detectors for API keys, tokens, private keys and passwords.
PolicyEach data type maps to mask, block or keep on-device. Secrets and prompt injection stop the request before anything is sent.
MaskValues become placeholders like <PERSON_1>. The same value always gets the same placeholder, so the answer still makes sense. The mapping stays in this page's memory.
RouteOrdinary requests go to the cloud model with placeholders only. With the on-device policy on, high-sensitivity requests never leave the machine.
Scan & unmaskThe reply is checked for secrets, then placeholders are swapped back to the real values for the user.
LogEvery request is recorded with its verdict, route and data types, giving compliance evidence without storing personal information.
This is the browser edition of a proof of concept. The desktop edition runs the same pipeline as an OpenAI-compatible proxy with Microsoft Presidio for name detection and a local model through Ollama, so any app can use it by changing one URL.