What is AI Runtime Boundary?
AI Runtime Boundary is a contextual architecture term for a trust boundary encountered while software is executing: for example, when a component invokes a service, tool, model, data store, or privileged operation. It is not necessarily a network perimeter.
The boundary should be mapped to the actual identities, interfaces, permissions, and data flows that apply at execution time. NIST SP 800-207 frames zero trust around explicit authentication and authorization before access to resources.
What is AI Runtime Boundary used for?
Teams use a AI Runtime Boundary to decide where runtime authorization, input and output validation, policy enforcement, logging, and containment are needed. It is useful in architecture reviews involving APIs, service-to-service calls, AI tools, and privileged automation. A clear definition names the component, resource, identity, expected action, and failure behavior so controls can be tested against the actual execution path.
