Reference data flows and threat models for security evaluations

Security is fundamental to building reliable AI agent systems. This article provides reference architectures and threat modeling approaches to help you identify security boundaries, assess risks, and implement appropriate controls in your agent solutions.

In this article, you learn how to:

• Map agent data flows to identify security control points.
• Apply threat modeling methodologies to agent architectures.
• Understand trust boundaries in custom engine implementations.

Agent reference data flow

Common agent data flows start with user prompts entering the system as raw data. The orchestrator, whether a language model or logical code flow, matches prompts to appropriate response logic through iterative intent detection and response matching processes.

Complex agents might need multiple iterations of intent detection and response matching when initial context isn't enough for accurate responses. For example, processing "summarize my emails" requires tool calls to retrieve grounding data that maps user identity to appropriate email accounts.

Each step in the data flow represents a potential security boundary and control point where you must enforce trust, traceability, and transparency requirements to maintain system integrity and user confidence.

Threat models

Threat modeling provides approaches to identifying and mitigating security risks in agent architectures. Use established tools like the Microsoft Threat Modeling Tool to create customized threat models for your specific agent implementations.

Custom engine agent threat model

Custom engine agents need comprehensive threat modeling to address service boundaries, data flows, and potential attack vectors across the entire agent ecosystem.

Threat models must account for the distributed nature of agent architectures, including client interfaces, orchestration services, language models, tool integrations, and data sources. Each component represents potential attack surfaces that require appropriate security controls and monitoring.