Code Archaeology

Mar 16, 2026 · Artificial Intelligence

How Deep Agents Implements Sub-Agent Delegation: Task Tool, State Isolation & System Prompt Injection

This article dissects Deep Agents' SubAgentMiddleware implementation, revealing how the task tool dynamically delegates complex work to isolated sub-agents with separate context windows, detailing dynamic tool construction, state isolation via excluded keys, system prompt injection for delegation guidance, and a Deep Research case study showing research-agent delegation in action.