The Architecture of Agent Behavior

Mon, 01 Jan 0001 00:00:00 +0000

Chapters 1 and 2 introduced the working style of agent systems: conversation, variation, feedback, revision, and human direction. Now we need to look underneath that experience.

An agent does not become capable because a class is named Agent or because a prompt says “you are a researcher.” The behavior comes from the arrangement of parts around the model:

goal
  ↓
role + instructions
  ↓
context + state
  ↓
model proposes
  ↓
runtime validates
  ↓
tool / memory / message
  ↓
environment observation
  ↓
state update
  ↓
continue, revise, coordinate, or stop

That is the architecture of agent behavior. The model supplies interpretation and generation. The prompt and context shape what the model sees. The runtime owns state, tool execution, permissions, memory retrieval, orchestration, and stopping rules. The human operator supplies purpose, constraints, judgment, and responsibility.

Agent Behavior on Programmer.ie: Modern AI programming

The Architecture of Agent Behavior