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 used to re-read its whole conversation. Now Haiku 5.5 writes it from short notes instead, so each update costs about 99% less.

The subagent itself keeps its own model. Sessions with background subagents used about 5% less of the limit, so the same limit gets you about 6% more prompts.

It's live for most Pro, Max and Ultra users and for everyone on Team and Enterprise. Update to v2.1.316+.