PII Signal

Overview

pii detects sensitive personal data in requests. Define PII rules under routing.signals.pii.

It uses the PII detector configured through global.model_catalog.system.pii_classifier.

Key Advantages

• Makes privacy-sensitive routing explicit.
• Lets decisions block, downgrade, or isolate risky traffic before it reaches a backend.
• Supports allowlists for low-risk identifier types.
• Keeps privacy policy reusable across routes and plugins.

What Problem Does It Solve?

Without a dedicated PII signal, privacy-sensitive traffic can reach the wrong model or plugin stack before detection happens. Ad hoc filters also make policy harder to audit.

pii solves that by turning personal-data detection into a reusable routing input.

When to Use

Use pii when:

• prompts may contain regulated or sensitive personal data
• some PII types are acceptable but others must trigger a safer route
• privacy-sensitive traffic needs different plugins or backends
• route policy depends on early PII detection

Configuration

routing:
  signals:
    pii:
      - name: restricted_pii
        threshold: 0.85
        include_history: true
        pii_types_allowed:
          - EMAIL_ADDRESS
        description: Sensitive prompts where only low-risk identifiers may pass through.

When pii_types_allowed is empty, any detected PII can cause the signal to match.

Dependencies and Limitations

The PII classifier processes the prompt and optional history. It is a routing control, not a substitute for redaction, encryption, access control, or data loss prevention. Calibrate thresholds by entity type. See a complete example: config/fragments/signal/pii/strict.yaml.