A capable agent handles its initial scope reliably. You provide a system prompt, grant access to a few tools, and it executes. But as you pile more operational responsibilities into a single context, it begins to slip. It drops early constraints, calls the right tool with the wrong arguments, or quietly contradicts a policy it adhered to three turns ago. When one context window is forced to act as a planner, a domain expert, and an executor all at once, reasoning degrades. The natural engineering instinct is to split the work across many specialised, tightly scoped agents.

Once an operation outgrows a single agent, the system requires a defined structural shape. You must establish clear boundaries around who makes routing decisions, who does the actual work, and who keeps the entire asynchronous process balanced. In agentic systems, this topology has an established name: the CWD pattern. We map out this baseline architecture in the anchor read below.

Deploying multiple agents is an architectural choice, not an automatic upgrade. Community design findings consistently show that a multi-agent system carries roughly an order-of-magnitude-plus more token cost than a single agent handling the same input. It introduces latency, requires rigorous state management across handoffs, and is strict overkill for simple or medium tasks. Often, one well-prompted agent remains the right answer. Moving from a single context to a distributed system is a ladder of fit, not of better.

When the workload genuinely demands multiple agents, this series covers how to sequence, trace, and secure them: