Claude Code's account says background subagent status updates now cost about 99% less

The post says a running subagent refreshes its status line every 30 seconds, and each refresh used to re-read the whole conversation. It says Haiku 5.5 now writes the status line from short notes, so "each update costs about 99% less." The post carried 686.6K views when we read it. It gives no measurement method and does not say how much of a whole session's usage the status updates accounted for, so the 99% figure applies to each update and not to total usage. The version of Claude Code that ships the change is not named in the post.

Why it matters: If long background subagents were using up your Claude Code limit faster than the work seemed to justify, status polling was a cost you could not see. Watch your own usage over the next few long runs before you count on a change in total spend.