Background subagents in Claude Code now use less of your usage limit. A running subagent updates its status line every 30 seconds, and each update …

Claude Code background subagents now utilize Claude 3.5 Haiku to update status lines via incremental notes rather than re-reading entire conversation histories. This architectural change reduces the token cost per 30-second status update by approximately 99%, preserving user usage limits during long-running agentic tasks.