Merlin's Whisper: Enabling Efficient Reasoning in Large Language Models via Black-box Persuasive Prompting

In three linesWhisper, an iterative prompting framework, reduces response length in large reasoning models (LRMs) via black-box persuasive prompting. 3x reduction on GSM8K for Qwen3; ~40% average token savings across benchmarks. Claude-3.7 and Gemini-2.5 achieve -46% to -50% on MATH-500.

Summary generated by Claude — human-verified