title
Architecture Decision Records
last_reviewed
2026-09-06
owner
agt-maintainers
Architecture Decision Records Key architectural decisions and their rationale. Each ADR follows the standard format: Context, Decision, Consequences.
!!! note "ADR process"
New ADRs use the repository template . Status values: accepted (implemented), proposed (under review), deprecated, superseded.
ADR
Decision
Area
ADR-0001 Use Ed25519 for agent identity signatures
Identity
ADR-0002 Four execution rings for runtime privilege separation
Runtime
ADR-0003 Keep IATP handshake under 200ms
Mesh
ADR-0004 Keep policy evaluation deterministic
Policy
ADR-0007 External JWKS federation for cross-org identity
Identity
ADR-0009 RFC 9334 (RATS) architecture alignment
Standards
ADR-0012 Cost governance via observability policies
SRE
ADR-0013 Fail closed on policy evaluation errors
Policy
ADR-0015 Pluggable external policy backends via protocol interface
Policy
ADR-0016 Trust ceiling propagation for delegated agents
Trust
ADR-0017 Merkle chain for audit tamper evidence
Audit
ADR-0018 Reconstructible Decision BOM over pre-built
Audit
ADR-0019 OTel BatchSpanProcessor pattern for event sink
Events
ADR-0020 Circuit breaker for event sink delivery
Events
ADR-0021 CloudEvents envelope for mesh audit
Audit
ADR-0022 Compliance framework auto-mapping
Compliance
ADR-0023 Append-only delta engine for hypervisor audit
Audit
ADR-0024 RL training governance with violation penalties
Lightning
ADR-0025 Structural typing for sink and source protocols
Architecture
ADR-0026 Azure Functions PDP behind AI Gateway for Foundry prompt-based agents
Policy
ADR-0030 Action-bound, fail-closed approval protocol
Policy / Audit
ADR-0031 Optional embedding evidence backend for prompt-injection detection
Security
ADR-0032 AGT emits TRACE v0.1 Trust Records per session
Audit / Standards
ADR
Decision
Area
ADR-0005 Add liveness attestation to TrustHandshake
Mesh
ADR-0006 Constitutional constraint layer as community extension
Policy
ADR-0008 Cross-org policy federation above identity
Policy
ADR-0010 TEE keystore with SEV-SNP attestation
Security
ADR-0027 Dual-stack migration for MCP 2026-07-28
MCP
ADR-0028 AGT Studio, a single unified UI for governance
UI
ADR-0029 Policy distribution and registries with verifiable trust
Policy / Supply chain
ADR-0033 Agent Learning governance integration boundary
Learning / Policy
ADR
Decision
Area
ADR-0011 Additive policy check contract
Policy
ADR-0014 Parent deny rules are immutable in policy merge
Policy