From classical AI theory to modern LLM stacks — trace the perceive–reason–act loop from first principles, classify the four agent architectures, and diagnose the failure modes that break real systems.
Every agent — classical or modern — runs this loop. Click each step to understand what happens at that moment.
If the first action fails, the agent tries a different approach instead of stopping.
Environment shifts require re-evaluation and new plans — only possible through iteration.
Multi-step goal pursuit requires continuous operation — not one-shot text generation.
Feedback from actions informs better decisions. The loop transforms prediction into behavior.
From classical AI theory (Russell & Norvig). Click each card to explore the architecture. Modern LLM agents are hybrid systems combining elements from all four.
Stimulus → Response. No memory, no planning.
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Compare state vs. goal. Introduce planning.
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Optimize trade-offs. Maximize a utility function.
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Update model from experience. Adapt over time.
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Review before the quiz — you'll be asked which capabilities each type has.
| Agent Type | Memory | Planning | Optimization | Learning |
|---|---|---|---|---|
| Reactive | ✗ | ✗ | ✗ | ✗ |
| Goal-Based | ~ | ✓ | ~ | ✗ |
| Utility-Based | ✓ | ✓ | ✓ | ✗ |
| Learning | ✓ | ✓ | ✓ | ✓ |
| Modern LLM Agent | ✓ | ✓ | ✓ | ✓ |
Diagram the agent loop for a customer service responder. Drag each behavior into the correct stage — Perception, Reasoning, Tools, Action, or Memory.
Most agent failures are architectural — not model errors. Drag each symptom into the failure mode it belongs to. Tap a header to reveal the prevention strategy.
Test your understanding. You need 70% or higher to mark this section complete.