> ## Documentation Index
> Fetch the complete documentation index at: https://docs.flexinference.com/llms.txt
> Use this file to discover all available pages before exploring further.

# PII Masking

We can mask personal data out of your prompt before the provider sees it. Each match becomes a stable placeholder such as `[EMAIL_1]`, so the model can still tell people apart. It covers emails, phone numbers, and patterns such as card numbers.

```json theme={null}
{ "pii_mask": true }
```

Masking runs on Managed Keys. On your own keys we forward your request untouched.

If your request sets `pii_mask` we follow it. If it doesn't, we follow your organization's default. If neither is set, masking is off. That means you can send `false` to turn masking off for one request when your organization has it on.

If masking is on and it fails, we stop the request rather than send it unmasked.