Agentic AI Reference Architecture

Observability & Evaluation · Software component

Tool Fault Injector

Software componentObservability & EvaluationObservability & Evaluationarc:ToolFaultInjector

A test component that replaces tool success responses with errors, empty results, unexpected formats, latency or unavailability during evaluation to exercise agent error handling.

Responsibility. Simulates tool failures during evaluation to test agent recovery behaviour.

Also known as: Tool Failure Simulator

sends data tois invoked bysends data toAgent Controller: sends data toAgent ControllerEvaluation Harness: is invoked byEvaluation HarnessReasoning Engine: sends data toReasoning Engine
Direct neighbourhood (hover for relationship types)

Relationships

is invoked by dependency

sends data to dynamic

Classification

Patterns
Fault injection
Risks mitigated
Untested recovery pathsError condition blindspotCircular reasoning on tool failure

Sources

  1. Ch3.8: T. Nguyen, "Action Accuracy Metrics," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 3.8. ISBN: 9798244538229.
  2. Ch3.9: T. Nguyen, "Reasoning Quality," in Mastering Agentic AI Systems: Guide for the NVIDIA NCP-AAI Exam, 1st ed. 2026, ch. 3.9. ISBN: 9798244538229.