BusMA swaps hierarchical agent routing for a shared bus

A new paper on arXiv by Yanwen Peng, Delvin Ce Zhang, Xi Wang and Nikolaos Aletras proposes borrowing a decades-old idea from computer architecture — the bus — to rewire how LLM agents talk to each other. The framework, called BusMA, lets any worker agent address any other through a shared channel instead of forcing every message through a manager or router.

The authors state the problem flatly: "Worker agents cannot directly consult specific "peers", and misrouted messages can propagate errors." Their alternative wires in three pieces: agent registration, message routing, and shared memory management. Workers post messages tagged with one of "four intents: discussion, challenge, guidance, and request for explanation," while a Chair agent monitors the shared memory to coordinate the group and "facilitate convergence among Workers."

The headline claim is terse. "BusMA consistently outperforms state-of-the-art HMW and RMP methods." That evaluation runs across 13 tasks spanning visual reasoning, mathematical reasoning, and knowledge retrieval, using what the abstract describes only as "two frontier LLMs." The baselines are the two protocols BusMA sets itself against: Hierarchical Manager-Worker and Router-based Message Passing. No per-task numbers appear in the abstract itself.