Independent Evidence Across System Boundaries.
How APP observes autonomous activity, maintains evidence-backed state and enables independent verification across system boundaries.
APP is designed around a simple constraint: no single system should be assumed to have complete visibility into an autonomous activity. The architecture collects evidence at multiple observation points while maintaining explicit provenance, uncertainty and correlation state.
A source-aware evidence architecture
- 01Agent activity
- 02Observation boundary
- 03APP runtime
- 04Evidence state
- 05Independent verifier
Runtime, gateway and provider observations can enter through distinct trust boundaries. Execution and outcome evidence are additional inputs when available. The implementing system makes enforcement decisions using evidence and local policy; APP is not the execution provider.
System Model
#system-modelAgent or autonomous system → observation boundary → APP runtime → evidence state → policy and evaluation → execution boundary → outcome → verifier.
Agent / Autonomous System
↓
Observation Boundary
↓
APP Runtime ── Policy / Evaluation
↓
Evidence State
↓
Execution Boundary → Outcome → APP VerifierOutside-In Architecture
#outside-in-architectureAPP observes systems it does not control at gateways, service boundaries, execution providers and protected interfaces. It forms the strongest defensible state from locally available evidence without requiring the external agent to become APP-native.
Inside-Out Architecture
#inside-out-architectureControlled runtimes can emit richer observations about agent identity, principal, delegated authority, intent, session state, policy context and tool activity.
Hybrid Architecture
#hybrid-architectureInside-Out and Outside-In evidence can be correlated into one activity representation while preserving which domain produced each observation.
APP Runtime
#app-runtimeThe runtime ingests observations, resolves evidence semantics, maintains current evidence-backed state and preserves immutable historical observations.
APP Verifier
#app-verifierThe verifier independently evaluates preserved evidence, signatures, provenance, freshness and claim support outside the environment that produced the original activity.
Trust Boundaries
#trust-boundariesOrganisations, vendors, infrastructure operators and execution providers may each be independently controlled domains. APP preserves these boundaries rather than assuming shared trust.
Failure and Partial-Evidence Behaviour
#failure-and-partial-evidence-behaviourMissing, stale or conflicting evidence produces explicit protocol state. APP does not silently substitute assumptions for unavailable facts.