A recent paper from Tsinghua and Renmin University caught my attention: Task-Decoupled Planning for Long-Horizon Agents. The core insight resonated with a problem I’ve been wrestling with on a Java code modernization project at work, and I think the pattern deserves more attention.

The Entangled Context Problem#

Most LLM agent architectures fall into two camps: step-wise planning (reactive, one step at a time) or one-shot planning (generate the whole plan upfront). Both share a fatal flaw: they maintain a monolithic reasoning context that spans the entire task history.