INP-01Direct prompt injection detection
Direct prompt injection detection is applied to user-provided inputs, using a combination of heuristic and classifier-based methods.
Direct injection, where a user attempts to override the system prompt through their input, is detected using a combination of heuristic and classifier-based methods. The agent does not disclose its system prompt or override its operating envelope in response to user-crafted inputs. Detection rates and false-positive rates are measured and reported.
Table INP-01.1 · Maturity criteria · v.1.3
L1 to L5 · the lowest level in scope caps the agentControls exist informally; documentation is incomplete; no consistent review.
Controls are written down; ownership is assigned; review cadence is defined.
Controls are followed in practice; evidence is collected; deviations are tracked.
Detection is applied to all user-facing input paths; detection rates and false-positive rates are measured; the detection pipeline is updated as new attack patterns are cataloged in SPC-08.
Control effectiveness is measured against documented thresholds; trends are reported.
Controls evolve based on incident learning; maturity gains are evidenced over time.
The v1.3 edition publishes a control-specific criterion at L3 (Operated). The other levels apply the general ladder to this control; see the maturity ladder.
Evidence an assessor asks for
- E.1
Detection is applied to all user-facing input paths.
- E.2
Detection rates and false-positive rates are measured.
- E.3
The detection pipeline is updated as new attack patterns are cataloged in SPC-08.
Table INP-01.2 · Framework mappings
7 of 7 frameworks carry a control-level referenceMappings are directional: meeting this control evidences but does not by itself satisfy the external requirement. A middle dot means no control-level reference is published at this edition; see the crosswalk.
Related controls and terms
Cite this control
Human Intelligence. HI-AAF v1.3, INP-01 Direct prompt injection detection. Public review edition, July 2026. https://humanintel.net/standard/inp/inp-01
Edition v.1.3 · July 2026 · Public review · Markdown · PDF
https://humanintel.net/standard/inp/inp-01
HI-AAF v1.3 is an independent framework published by Human Intelligence. It is not affiliated with NIST, ISO, AICPA, or any government or accreditation body. The framework is offered openly for review during the current draft cycle.