Deny-List Content Filter

Software componentSafety & SecuritySafety, Security & Governancearc:DenyListContentFilter

A content safety filter that blocks text matching any entry of a deny list of forbidden words, phrases or compiled regular expressions.

Responsibility. Blocks text containing enumerated forbidden terms or patterns.

Also known as: Keyword filter, Pattern-matching filter, Profanity filter, Regex filter

Variant of Content Safety Filter abstract

When to choose. Choose when microsecond latency, implementation simplicity and deterministic, auditable behaviour matter, e.g., as a fast first-pass check for blatant violations before more expensive ML classifiers; avoid as sole defense where context matters or adversaries use misspellings and character substitutions.

Direct neighbourhood (hover for relationship types)

Relationships

is configured by structural

Content Deny List Ch9.1 Ref9.04

is invoked by dependency

Input Rail Ch9.1

alternative to variability

Design guidance

SHOULD use word-boundary patterns to avoid substring false positives (e.g., 'kill' matching 'skill').
SHOULD precompile patterns once at initialization and match case-insensitively.
SHOULD NOT be the only defense, because it is brittle against misspellings, character substitutions and Unicode lookalikes and lacks context awareness.

Quantitative guidance

As stated by the sources; verify before use.

Keyword and regex patterns execute in microseconds, versus milliseconds for neural classifiers (Ch9.1).

Classification

Patterns: Deny listingWord-boundary regex matching
Technologies: better-profanity
Quality attributes: Performance efficiency (ISO/IEC 25010)Reliability (ISO/IEC 25010 | NIST AI RMF: valid and reliable)Transparency and accountability (NIST AI RMF: accountable and transparent)Maintainability (ISO/IEC 25010)
Risks mitigated: ProfanityKnown attack signaturesBlatant policy violations

Sources

Ch9.1: T. Nguyen, "Output Filtering and Content Moderation," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 9.1. ISBN: 9798244538229.
Ref9.04: "Safety Guardrails Implementation for Agent Systems," unpublished reference note (04-Safety-Guardrails-Implementation.md), Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam supplementary materials, 2026. unpublished note