Agent Unveiled: Principles, Architecture, and Engineering Practices
This article systematically examines the underlying architecture and engineering practices of agent systems. Starting from a stable agent loop, it contrasts workflows with agents, explains five control patterns, and emphasizes that the harness (evaluation baselines, execution boundaries, feedback, and fallbacks) often matters more than the model itself. It details context engineering via layered management and three compression strategies to prevent context rot, ACI‑oriented tool design, a four‑type memory system with consolidation, long‑task state externalization across sessions, protocol‑based multi‑agent coordination, eval frameworks (Pass@k and Pass^k), and event‑driven observability. Finally, it shows how these principles are implemented in OpenClaw, providing a practical reference for engineers building robust agents.