Claude Code Background Subagent Status Lines Now Written by Haiku 5.5: About 99% Cheaper per Update, About 6% More Prompts per Limit
On November 4 ClaudeDevs, Anthropic's official developer account, said the status line that a background subagent in Claude Code refreshes every 30 seconds used to re-read its whole conversation each time, and is now written by Haiku 5.5 from short notes, so each update costs about 99% less. Anthropic says sessions with background subagents used about 5% less of the limit, giving about 6% more prompts on the same limit. It is live for most Pro, Max and Ultra users and everyone on Team and Enterprise, on v2.1.316 or later.
Key Takeaways
- A background subagent refreshes its status line every 30 seconds, and each refresh used to re-read the subagent's whole conversation
- Haiku 5.5 now writes the status line from short notes, which Anthropic says makes each update about 99% cheaper
- The subagent itself keeps its own model; only the status line is written by Haiku 5.5
- Anthropic says sessions with background subagents used about 5% less of the limit, so the same limit gives about 6% more prompts
- It is live for most Pro, Max and Ultra users and everyone on Team and Enterprise; update to v2.1.316 or later



