IBM Research fine-tunes a 20B open model to build slide decks in house style

IBM Research published a technical article on Palette, a 20-billion-parameter open-weight model fine-tuned to build slide decks that follow a given design language, demonstrated with the IBM Design Language. The work splits the task between two roles handled by a single LoRA adapter: a designer that writes a structured JSON brief covering palette, type and each slide's layout and content, and a coder that turns one slide's spec into pptxgenjs JavaScript. A harness renders each slide, flags overlap or overflow, and keeps an edit only when the checker confirms improvement. On PresentBench, Palette placed first in two of three domains measured.