π€ AI Summary
To address inconsistent cross-lingual performance of multilingual large language models (LLMs) on knowledge extraction tasks, this paper proposes a parameter-free, gradient-driven multilingual trigger word learning method. The approach dynamically identifies input language, optimizes lightweight language-adaptive triggers via gradient-based search, and automatically selects and injects themβwithout modifying any model parameters. Its core innovation is the first gradient-driven prompt generation mechanism, enabling efficient, language-aware prompt engineering. Evaluated on the MMLU benchmark across 15 languages, the method achieves accuracy improvements of 3.7%β19.9% on two ~1B-parameter models, significantly enhancing cross-lingual reasoning consistency. It establishes a scalable, low-overhead paradigm for multilingual prompt optimization.
π Abstract
Large language models (LLMs) showcase increasingly impressive English benchmark scores, however their performance profiles remain inconsistent across multilingual settings. To address this gap, we introduce PolyPrompt, a novel, parameter-efficient framework for enhancing the multilingual capabilities of LLMs. Our method learns a set of trigger tokens for each language through a gradient-based search, identifying the input query's language and selecting the corresponding trigger tokens which are prepended to the prompt during inference. We perform experiments on two ~1 billion parameter models, with evaluations on the global MMLU benchmark across fifteen typologically and resource diverse languages, demonstrating accuracy gains of 3.7%-19.9% compared to naive and translation-pipeline baselines.