🤖Multi-Agent Systems Hit Three Patterns and Three Failure Modes Developers Must Handle

Your demo agent won't survive production coordination

A single agent with a clear goal, a few tools, and a decent system prompt will impress anyone in a five-minute walkthrough. That's the trap. The moment you run more than one agent, you've added a coordination problem on top of the reasoning problem, and coordination is where almost all the real engineering time goes. If you're building agent workflows, you need to pick an architecture before you write code. Orchestrator-Worker maps cleanly onto how a human manager delegates: one orchestrator splits the task, dispatches subtasks to specialist workers, and merges the results. Blackboard drops the hierarchy entirely, letting agents read and write a shared state store and decide for themselves when to contribute. Pipeline is the boring one, a fixed chain of agents passing output forward, and it's the easiest to evaluate. The catch? Each pattern fails differently. Orchestrators become bottlenecks. Pipelines go rigid the second a task doesn't fit a fixed sequence. Blackboards invite conflicting concurrent writes. Failure modes you'll actually hit include infinite delegation loops, runaway cost from re-invocation, conflicting writes, and error propagation between agents. The fixes are boring and in code: hard caps on delegation depth, a per-task token or cost budget, and a defined human-escalation path.