Dual-Use Filter

The dual-use-filter policy matches content against a list of dual-use terms. If you do not configure blocked_terms, the gateway falls back to a built-in reference list that includes terms such as weapon, explosive, bioweapon, nerve agent, centrifuge, uranium enrichment, and NATO classification phrases.

Configuration

pack:
  name: dual-use-filter-example
  version: 1.0.0
  enabled: true

policies:
  chain:
    - dual-use-filter

policy:
  dual-use-filter:
    blocked_terms:
      - centrifuge
      - precursor chemical
      - maraging steel
      - uranium enrichment
    action: block
    fuzzy_matching: true
    max_distance: 2

Fields

Field	Type	Description	Default
blocked_terms	string[]	Terms to match. If omitted, the gateway uses its built-in reference list.	built-in list
action	block | redact	block stops the request. redact returns a redact verdict for the gateway redaction path.	block
fuzzy_matching	boolean	Enable near-match detection.	false
max_distance	integer	Maximum edit distance used with fuzzy matching.	1

Built-in reference terms

The default list includes a broad starter set such as:

• weapon
• explosive
• bioweapon
• nerve agent
• dual-use / dual use
• nato restricted, nato confidential, nato secret
• precursor chemical
• cyber surveillance
• intrusion software
• nuclear material
• centrifuge
• uranium enrichment
• plutonium
• heavy water
• maraging steel
• carbon fibre / carbon fiber

Use Cases

Block with custom terms

pack:
  name: export-control
  version: 1.0.0
  enabled: true

policies:
  chain:
    - dual-use-filter
    - entity-list-filter
    - itar-ear-filter

policy:
  dual-use-filter:
    blocked_terms:
      - uranium hexafluoride
      - thermal imaging
      - night vision
    action: block

Use the built-in defaults

pack:
  name: default-dual-use-guard
  version: 1.0.0
  enabled: true

policies:
  chain:
    - dual-use-filter

policy:
  dual-use-filter: {}

How It Works

1. Keeptrusts joins the current message content into a single text buffer.
2. It loads blocked_terms, or the built-in reference list when blocked_terms is omitted.
3. It checks for exact case-insensitive matches, and optionally fuzzy matches within max_distance.
4. On a match it returns block or redact according to action.

Best Practices

• Keep blocked_terms focused when you override the defaults.
• Use block when you need deterministic enforcement of the matched term itself.
• Treat redact as a softer verdict that depends on the gateway's redaction handling rather than a dual-use-specific replacement marker.
• Pair this policy with entity-list-filter and itar-ear-filter for stronger export-control coverage.

Next steps

• Entity List Filter — Restricted-party screening
• ITAR/EAR Filter — Export-control term blocking
• Embedding Detector — Similarity-based matching
• DLP Filter — Custom regex and term controls