Chapter 4: Multi-Agent Systems Without Theater¶
Multi-agent systems are where the gap between demo and production is widest. This chapter draws the line between coordination patterns that solve real problems and complexity theater that looks impressive but fails at 2 AM.
What this chapter covers¶
- When multi-agent is justified -- the specific conditions where a single agent cannot hold the task
- When multi-agent is theater -- recognizing unnecessary decomposition
- Core patterns -- orchestrator, message contracts, and agent specialization
- The working example -- retriever, reasoner, and verifier on the document intelligence task
- The comparison -- single-agent vs multi-agent on accuracy, cost, and latency
- Coordination overhead and cost explosion -- the real price of multi-agent
- Failure modes -- what goes wrong when agents coordinate
Code companion¶
The working code for this chapter is in src/ch04_multiagent/:
contracts.py-- Agent message contractsagents.py-- Specialized agents (retriever, reasoner, verifier)orchestrator.py-- Multi-agent orchestrationcompare.py-- Single vs multi-agent comparisonrun.py-- Executable example
Get the full chapter¶
The complete chapter text is available in the book.