An agentic swarm is a supervised group of coding agents working one job: a partitioner splits it into tasks with verification commands, agents execute in isolated workspaces, liveness is tracked by heartbeat, failures walk a bounded repair ladder, and only verified work reaches an integration branch. The supervisor (not any single agent) owns budgets, placement, retries and the merge gate. Swarms pay off on partitionable work (modules, audits, migrations) and lose to a single agent on tightly coupled edits.