Swarm Topology How Agents Should Talk to Each Other

The shape of your agent swarm decides whether it scales or collapses on the first failure. The topology is the architecture — and most swarms pick it by accident.

Multi-agent topology is the decision everyone makes and nobody discusses. A hub-and-spoke swarm fails differently from a mesh, and a pipeline fails differently from both. The topology should be a design choice, not a default.

Issue-tree the options:

• **Hub-and-spoke.** One orchestrator routes to specialists. Wins when you need central control and a clear audit path. Loses when the hub becomes the bottleneck.
• **Pipeline.** Agents hand off in sequence. Wins when the workflow is linear and each step is well-scoped. Loses when a step fails and blocks everything downstream.
• **Mesh.** Agents talk peer-to-peer. Wins when the work is exploratory and collaborative. Loses when nobody can answer "who decided what."

The topology that survives production is the one designed for failure, not for the happy path. Hub-and-spoke with a fallback orchestrator; pipeline with bypass and escalation at each step; mesh with a shared log so every decision is reconstructable.

• Who takes over when the hub fails?
• Where does a stuck step escalate?
• Where is the shared decision log?

The audit path is the design constraint that picks the topology for you. If you need a single reconstructable decision log — which regulated work always does — mesh becomes expensive and hub-and-spoke becomes cheap, regardless of performance.

FACTA's multi-agent work designs swarms where each agent has a clear role, scope, and handoff — with observability and guardrails. The topology is a design decision made against the failure modes, not a framework default.

Swarm topology is the architecture, and it should be a design choice. Pick it against the failure modes and the audit path — not against the framework's default.