Mask PII in free text before you send it to an LLM or write it to a log. Pattern-based detection (not ML): emails, phone numbers (Google libphonenumber), IBANs (mod-97), payment cards (Luhn), URLs and IPs. Choose types[] and mode: mask (j***@d***.com, readable), remove, or label ([EMAIL_1], re-identifiable by index). Names and postal addresses are out of scope. The input text is never logged or stored.