ICL-Markup: Structuring In-Context Learning using Soft-Token Tags

Large pretrained language models (PLMs) can be rapidly adapted to a wide variety of tasksvia a text-to-text approach, where the instruction and input are fed to the model in natural language.Combined with in-context learning (ICL), this paradigm is impressively flexible and powerful.However, it also burdens engineers with an overwhelming amount of choices,many of them arbitrary.Inspired by markup languages like HTML, we contribute a method of using soft-token (a.k.a tunable token)tags to compose prompt templates.This approach reduces arbitrary decisionsand streamlines the application of ICL.Our method is a form of meta-learning for ICL;it learns these tags in advance during a parameter-efficient fine-tuning ``warm-up'' process.The tags can subsequently be used in templates for ICL on new,unseen tasks without any additional fine-tuning. Our experiments with this approach yield promising initial results.Improving PLM performance in important enterprise applications such as few-shot and open-world intent detection, as well as text classification in a legal domain.