When Learned Context Planning Fails to Beat Strong Retrieval: A Controlled Study of Planning, Routing, and Reranking for Long-Context QA

arXiv:2609.26976 · cs.CL, cs.IR · Submitted 2026-09-22 · Read on arXiv

cs.CL, cs.IR

Submitted: 2026-09-22

Updated: 2026-09-22

Code: https://github.com/aapplepku/context-planning-vs-retrieval

Terminology

• Accuracy — 6× in this paper · explained in 1 episode
• Trace — 5× in this paper · explained in 2 episodes
• Transformer — 4× in this paper · explained in 2 episodes
• Adaptation — 1× in this paper · explained in 1 episode
• Distillation — 1× in this paper · explained in 2 episodes
• Embeddings — 1× in this paper · explained in 2 episodes
• Fine-Tuning — 1× in this paper · explained in 5 episodes
• Generative AI — 1× in this paper · explained in 2 episodes
• Parameter-Efficient Fine-Tuning — 1× in this paper · explained in 2 episodes
• RAG — 1× in this paper · explained in 3 episodes
• Reasoning Traces — 1× in this paper · explained in 3 episodes
• Robustness — 1× in this paper · explained in 5 episodes
• alpha — 1× in this paper · explained in 1 episode

Sources

• LongBench v2: Towards Deeper Understanding and Reasoning on Realistic Long-context Multitasks
• Qwen2.5 Technical Report

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