Claude Code cuts subagent update cost 99%, session use 5%

Each 30-second status update from a background subagent in Claude Code costs about 99% less, because Haiku 5.5 writes it from short notes instead of re-reading the whole conversation. The figure that reaches your limit is smaller: Anthropic says sessions with background subagents used about 5% less of it.

That works out to about 6% more prompts on the same limit. The subagent doing the work keeps its own model, and only the status line goes to Haiku 5.5.

It’s live for everyone on Team and Enterprise and for most Pro, Max and Ultra users on v2.1.316 or later.