The article addresses this specific use under the 'Claude Code Subagents' section.
> The benefit of having a subagent in this case is that all the subagent’s investigative work does not need to remain in the history of the main agent, allowing for longer traces before running out of context.
History is nothing just list of dict containing role and messages? You can evict any entry at any point.
This very narrow very specific single-purpose task-oriented subagent was one of the first things talked about in this every lovely recent & popular submission (along with other fun to read points):
What makes Claude Code so damn good (and how to recreate that magic in your agent)!? https://minusx.ai/blog/decoding-claude-code/ https://news.ycombinator.com/item?id=44998295