Agent Architectures and Patterns
Design patterns for agents
Common architectures
There are several common agent patterns. A reactive agent responds quickly to what it sees. A planning agent creates a strategy first. A tool-using agent focuses on external actions. A multi-agent system uses several specialized agents that cooperate.
Architecture patterns
Reactive
- Fast response
- Simple design
- May struggle with long tasks
Planning
- Better for multi-step tasks
- More organized
- May take more time up front
No one pattern wins everywhere
The best architecture depends on task complexity, risk, speed, and how much control you want.
Role-based agents
In a multi-agent setup, one agent might research, another summarize, and a third verify. This division of labor can improve quality when tasks are naturally separable.
Which architecture is usually best for a very simple, immediate response task?
Reactive agents are designed for quick response with low overhead.
Correct answer: Reactive
Why might a multi-agent system be useful?
Specialization can improve coverage and quality.
Correct answer: Because different agents can specialize in different parts of a complex job.
Design tradeoff
More structure often improves reliability, but it can also add complexity. Good engineering balances simplicity with capability.
AGENT ARCHITECTURES
Common patterns used to structure real-world agent systems
Single Agent (ReAct)
One agent, one LLM, one tool loop. Simplest pattern. Best for focused, bounded tasks.
Orchestrator + Workers
Manager agent delegates to specialized sub-agents. Each worker handles one skill area.
Pipeline (DAG)
Agents form a directed graph. Output of one becomes input of the next. Predictable, auditable.
Peer-to-Peer (Swarm)
Agents communicate as peers. Emergent, harder to control. Used in research and simulation.
Architecture Comparison Matrix
| Pattern | Complexity | Scalability | Debuggability | Best For |
|---|---|---|---|---|
| Single ReAct | 🟢 Low | 🔴 Low | 🟢 Easy | Focused tasks |
| Orchestrator | 🟡 Medium | 🟢 High | 🟡 Medium | Multi-domain |
| Pipeline DAG | 🟡 Medium | 🟢 High | 🟢 Easy | Production pipelines |
| Swarm | 🔴 High | 🟢 Very High | 🔴 Hard | Research / Simulation |