DRT replaces long chain-of-thought with compact structured traces and reports 5.5x better token efficiency
AspireAI community · arXiv
Most multimodal reasoning is expressed in natural language, which costs tokens and dilutes the visual evidence in the trace. Dense Reasoning Trace reformulates reasoning as compact structured traces that separate visual observations from logical deductions, with symbolic connectors and concise intermediate states. A dense trace initialisation phase teaches the format, and Trace-Grounded Reinforcement Learning builds reference traces through a tri-perspective verification pipeline before applying Trace-Grounded GRPO with structured rewards. On challenging multimodal reasoning benchmarks the authors report a 5.5x token-efficiency improvement while gaining 1.3 accuracy points over the Qwen3-VL baseline, with code and data released. The gain is measured against one baseline family, so the size of the win may shift on other models.
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