Architecture
Purpose of This Document
Reference Foundations
1) Event-Driven Architecture
2) Workflow Engine Principles
3) RBAC Standard Model
4) Policy as Code
5) Tooling Protocol Foundation
6) Agent-to-Agent Interoperability Foundation
Reference Mapping by Architecture Topic
Architecture Consideration Checklist
1) Control Plane [ref: event-driven]
2) Event-Driven Runtime [ref: event-driven]
3) Run/Session Lifecycle [ref: workflow-engine]
4) Queue & Concurrency Model [ref: workflow-engine, event-driven]
5) Runtime vs Business Layer Boundary [ref: architecture-principle]
6) Policy & Access Control (RBAC/RoleBinding) [ref: nist-rbac, opa]
7) Organization Context Model [ref: nist-rbac, opa]
8) Messages [ref: event-driven]
9) Tools (MCP-aligned) [ref: mcp]
10) Memory [ref: architecture-principle]
11) Skills [ref: architecture-principle]
12) A2A Communication [ref: a2a]
13) Observability & Audit [ref: event-driven, workflow-engine]
14) Reliability (Retry/Idempotency/Recovery) [ref: workflow-engine]

Architecture

Purpose of This Document

This page is intentionally rough. The goal is not to finalize implementation details. The goal is to identify:

what architecture topics must be considered,
why each topic matters,
what should be detailed in follow-up threads.

Reference Foundations

1) Event-Driven Architecture

Martin Fowler: https://martinfowler.com/articles/201701-event-driven.html
Microsoft Azure Architecture Center: https://learn.microsoft.com/en-us/azure/architecture/guide/architecture-styles/event-driven

2) Workflow Engine Principles

Temporal: https://temporal.io/blog/workflow-engine-principles

3) RBAC Standard Model

NIST RBAC: https://www.nist.gov/publications/nist-model-role-based-access-control-towards-unified-standard

4) Policy as Code

Open Policy Agent (OPA): https://www.openpolicyagent.org/docs/latest/

5) Tooling Protocol Foundation

Model Context Protocol (MCP): https://modelcontextprotocol.io/introduction

6) Agent-to-Agent Interoperability Foundation

Agent2Agent Protocol (A2A): https://github.com/a2aproject/A2A

Reference Mapping by Architecture Topic

Control Plane / Event-Driven Runtime / Messages / Observability → event-driven
Run/Session Lifecycle / Reliability → workflow-engine
Policy & Access Control / Organization Context → nist-rbac, opa
Tools → mcp
A2A Communication → a2a
Memory / Skills → architecture-principle

Reference tags:

event-driven, workflow-engine, nist-rbac, opa, mcp, a2a, architecture-principle

Architecture Consideration Checklist

1) Control Plane `[ref: event-driven]`

2) Event-Driven Runtime `[ref: event-driven]`

3) Run/Session Lifecycle `[ref: workflow-engine]`

4) Queue & Concurrency Model `[ref: workflow-engine, event-driven]`

5) Runtime vs Business Layer Boundary `[ref: architecture-principle]`

6) Policy & Access Control (RBAC/RoleBinding) `[ref: nist-rbac, opa]`

7) Organization Context Model `[ref: nist-rbac, opa]`

8) Messages `[ref: event-driven]`

9) Tools (MCP-aligned) `[ref: mcp]`

10) Memory `[ref: architecture-principle]`

11) Skills `[ref: architecture-principle]`

12) A2A Communication `[ref: a2a]`

13) Observability & Audit `[ref: event-driven, workflow-engine]`

14) Reliability (Retry/Idempotency/Recovery) `[ref: workflow-engine]`

Development Acknowledgements

⌘I