Architecture Decision Records
August 4, 2026 ยท View on GitHub
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 Status values: accepted (implemented), proposed (under review), deprecated, superseded.
Accepted
| 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-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-0014 | Parent deny rules are immutable in policy merge | 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 |
Proposed
| ADR | Decision | Area |
|---|---|---|
| ADR-0005 | Add liveness attestation to TrustHandshake | Mesh |
| ADR-0006 | Constitutional constraint layer as community extension | Policy |
| ADR-0007 | External JWKS federation for cross-org identity | Identity |
| ADR-0008 | Cross-org policy federation above identity | Policy |
| ADR-0010 | TEE keystore with SEV-SNP attestation | Security |
| ADR-0011 | Additive policy check contract | Policy |
| ADR-0026 | Azure Functions PDP behind AI Gateway for Foundry prompt-based agents | Policy |
| 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-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 |