How the pieces fit together

The relationship between the two layers is the thing to take away. The four agentic patterns (reflection, planning, tool use, multi-agent) are capabilities an individual agent can have. The five workflow patterns (prompt chaining, routing, parallelization, orchestrator-workers, evaluator-optimizer) are ways to arrange agents and calls into a system. Every agentic RAG architecture in the next chapter is a specific recipe combining these: a router architecture is mostly the routing pattern, a corrective architecture is mostly the evaluator-optimizer pattern, a hierarchical architecture is the orchestrator-workers pattern applied in tiers, and so on.

Holding this in mind turns the long taxonomy of Chapter 3 from a list to memorize into a small set of building blocks you can recognize being recombined.