We built a web app to let students interact with and visualize the Beam Search algorithm for next word selection in LLMs. Users enter a text sequence and the app queries GPT-2 to extend the sequence. The intermediate probabilities are extracted from the model and displayed in an animated tree graph that visualizes the generation and selection of beams.

The Beam Search Visualizer is available online at https://tjefferson401.github.io/probability-tiptap/#/beamsearch. Students in Stanford's CS 109: Probability for Computer Scientists can use the visualizer to gain an appreciation for the Beam Search algorithm and how LLMs work.