One lead. Many helpers.
Subagents are helpers the main agent can hand a task to. Each gets its own fresh context and reports back a summary, keeping the main session clean.
Reviewer
Read-Only
Checks changes for bugs and security.
Test writer
Focused
Writes tests for what was just built.
Explorer
Research
Maps a codebase and reports back.
Setting one up
Ask Claude to create one, or add a file yourself.
Saved in .claude/agents/ as a file.
Give it a clear job and only the tools it needs.
Source: Anthropic Claude Code Docs ↗
Parallel work still needs one reviewer: you.