Do Multi-Agent Systems Actually Beat a Single Strong Agent?

There’s a lot of excitement around multi-agent architectures right now, but I’m wondering if we’re sometimes adding agents simply because we can.

A single strong agent with good tools, memory, and a well-designed workflow can already handle surprisingly complex tasks.

Multi-agent systems obviously make sense when work can be split into genuinely independent or specialized tasks. But then you introduce coordination, communication overhead, state management, and more potential failure points.

So where does the trade-off actually make sense?

For those building agents:

• When has multi-agent genuinely improved your results?
• When did you find a single agent was actually better?
• Does specialization justify the added coordination overhead?
• At what point does “multi-agent” become unnecessary architecture?

Curious to hear from people who have actually tested both approaches rather than just what looks better in demos.