What are subagents?

Core Concept

• Specialized assistants that Cloud Code delegates tasks to
• Each runs in its own isolated conversation context window
• Returns only a summary to the main thread; intermediate work stays isolated

Key Advantages

• Context window management: Prevents main context from being cluttered with tool calls, file reads, and search results
• Efficiency: Get focused answers without storing the entire exploration journey
• Scalability: Enables longer Cloud Code sessions without context bloat

How Subagents Work

• Receive two inputs: custom system prompt (from config) + task description (from parent agent)
• Work autonomously without exposing intermediate steps to main conversation
• Entire subagent conversation is discarded after returning summary

Trade-off

• Benefit: Clean main context window
• Cost: Main window loses visibility into how conclusions were reached

Built-in Subagents

• General Purpose: Multi-step tasks requiring exploration and action
• Explore: Fast codebase searching
• Plan: Research and analysis before presenting plans

Custom Subagents

• Can create your own with custom system prompts and tool access

Takeaways

• Subagents are specialized assistants that isolate work: Each runs in its own conversation context, keeping intermediate steps (tool calls, searches, file reads) hidden from the main thread—only returning a summary.

• They solve context window bloat: By delegating focused tasks to subagents, the main conversation stays clean and efficient, enabling longer Cloud Code sessions without losing context space.

• **Trade-off: Cleanliness vs. transparency**: You gain a clutter-free main window but lose visibility into how conclusions were reached—the entire subagent conversation is discarded after summarizing.

• Built-in subagents handle common patterns: General Purpose (multi-step tasks), Explore (codebase searching), and Plan (research/analysis) cover typical workflows.

• Customizable for your needs: You can create custom subagents with tailored system prompts and specific tool access for domain-specific tasks.