[Claude Code] Subagents support

[TylerLeonhardt]

Overview

Implement support for Claude Code subagents, allowing specialized agents to be spawned for specific tasks.

Background

The Claude Agent SDK supports subagents for delegating specialized tasks. This enables a parent agent to spawn focused child agents for specific operations.

Current State

• No subagent support currently implemented
• Claude Code SDK provides subagent capabilities per official documentation

Tasks

Research

• Review Claude Code SDK subagent documentation
• Understand subagent lifecycle management
• Document available subagent patterns

Implementation

• Enable subagent spawning in ClaudeCodeSession
• Handle subagent message routing
• Implement subagent progress/status display in UI
• Handle subagent tool confirmations
• Manage subagent lifecycle and cleanup

UI Considerations

• How to display subagent activity in chat UI
• Differentiate parent vs. subagent messages
• Show subagent hierarchy/tree if nested

Use Cases to Support

• Specialized coding agents (test writing, refactoring, etc.)
• Research agents for documentation lookup
• Review agents for code analysis
• (Document other use cases)

Questions

• Should subagents have separate tool confirmation policies?
• How to visualize subagent hierarchy?
• Should users be able to interact directly with subagents?

Related Files

• src/extension/agents/claude/node/claudeCodeAgent.ts
• src/extension/agents/claude/node/claudeCodeSdkService.ts

References

• Agent SDK Subagents documentation

Dependencies

• SDK update
• Session API modernization (potentially)

[TylerLeonhardt]

I've seen the Task tool run so I know subagents are at least useable. So this may be done enough, but I would like to smoke test them and see if we can add a picker to switch the agent.

[TylerLeonhardt]

You can also simply ask to run a specific agent and it'll work