28 · Single vs Multi-Agent Systems
Choose the simplest architecture that solves the problem.

This helps you choose the simplest architecture that solves the problem: start with one agent and add more only when you need to. It compares single-agent and multi-agent systems and their trade-offs.
In simple terms
Start with a single agent; move to multi-agent only when the problem truly needs it.
How it works
- 1Single agent (do-it-all): one agent plans, uses tools and gets the job done.
- 2Multi-agent (specialists): a supervisor/orchestrator coordinates research, analysis, execution and review agents.
- 3Multi-agent patterns: supervisor (centralized), hierarchical, peer-to-peer, pipeline, parallel, reflection/critic.
- 4Design guidelines: start single, add specialization, give clear roles and structured output.
Key points
- Use single agent for simple/moderate tasks, few tools, low coordination.
- Use multi-agent for complex, multi-domain, long-running or high-accuracy work.
- Trade-offs: multi-agent adds latency, cost and complexity but scales specialization.
- Design for impact, not for a demo.
Why it matters
Over-engineering with many agents adds cost and fragility. Choosing single vs multi-agent deliberately keeps systems simple, debuggable and reliable.
Frequently asked questions
- When should I stay single-agent?
- For straightforward tasks with few tools and low coordination — it's simpler and cheaper to debug.
- What do multi-agent systems cost?
- More latency, tokens and complexity, in exchange for specialization and scale on complex goals.
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3 · LangChain Ecosystem
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4 · LangGraph Orchestration
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5 · AWS Bedrock Integration
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6 · Amazon AgentCore
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