Large Language Models (LLMs) have evolved rapidly over the past few years and there have already been many practical applications in a variety of fields. Though Python is recognized as a de facto standard language to use LLMs, we are Rubyists so we would like to explore how we use LLMs in the Ruby language.

In this session, I will explain the basics of Large Language Models(LLMs), and then cover Langchain.rb as a tool to use LLMs from the Ruby language. The development of RBS Goose, which is a tool to refine RBS type signatures, is a good practical example. We’ll share how it works including prompt construction, as well as the tips for LLMs development and our evaluation of its performance, including accuracy and speed, at the combination of various prompts, Few-Shot examples, and LLMs.