Isolated Subagent Boundaries (Principle)
- Entity ID:
ent-20260423-c003d100000c - Type:
decision - Scope:
private - Status:
active
Description
Design principle #12. Answers 'Do subagents share the parent's context and permissions, or operate in isolation?' Claude Code spawns subagents via AgentTool that re-enters queryLoop() with an isolated context window and returns only a summary to the parent. Serves Reliability, Safety, and Capability.
Key claims
- Subagent sessions cost approximately 7x the tokens of a standard session
Relations
- Safety, Security, and Privacy (Value) --[motivates]--> Isolated Subagent Boundaries (Principle)
- Reliable Execution (Value) --[motivates]--> Isolated Subagent Boundaries (Principle)
- Isolated Subagent Boundaries (Principle) --[instantiated_by]--> Sub-Agent Context Isolation Property
- Subagent-Architecture Decision --[answered_by]--> Isolated Subagent Boundaries (Principle)