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The Mask PII guardrail detects and masks personally identifiable information (PII) in user input before it reaches the model. Its purpose is to ensure assistants do not process data that could compromise privacy or expose regulated information. This guardrail scans incoming text and automatically replaces sensitive data with safe placeholders, preserving the user’s intent without revealing their information. Mask PII configuration interface in Devic

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What Mask PII Detects

Mask PII analyzes user input and replaces any detected personally identifiable information with a generic placeholder.
Examples:
  • “Mi tarjeta es 4111 1111 1111 1111” → “My card is [CREDIT_CARD_NUMBER]”
  • “Vivo en 123 Main St, NY” → “I live at [LOCATION]”
  • “Mi email es john.doe@example.com” → “My email is [EMAIL_ADDRESS]”
This allows the assistant to work with the message without exposing real data.

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Configurable PII Categories

Devic allows enabling or disabling specific types of PII that will be masked in user inputs.
Available types include:

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Global Identifiers

  • Credit card number
  • Cryptocurrency wallet
  • Date and time
  • Email address
  • IBAN
  • IP address
  • Location
  • Medical license number
  • Person name
  • Phone number
  • URL

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United States

  • Bank account number
  • Driver’s license number
  • ITIN
  • Passport number
  • Social Security Number

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United Kingdom

  • NHS number
  • National Insurance Number
Users can individually select each category or enable Select All from the interface. Example of selectable PII categories in Devic

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When to Use Mask PII

Mask PII is recommended for assistants that:
  • Process instructions that may contain personal data.
  • Operate in regulated environments (GDPR, HIPAA, internal compliance).
  • Interact with end users and must avoid storing or transmitting sensitive information.
  • Execute automated workflows where data must remain anonymized.

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How to Configure It

To enable Mask PII in an assistant:
  1. Open the assistant from the sidebar.
  2. Click the options menu (⋮) in the top-right corner.
  3. Select Guardrails.
  4. Click Add guardrail.
  5. Choose Mask PII.
  6. Select the entities you want to mask.
  7. Save your configuration.

Next: Moderation

Learn how to block sensitive or inappropriate content using the Moderation guardrail.