Flint is an intermediate visualization language that compiles compact, semantic chart specifications into complete configurations for rendering backends including Vega-Lite, Apache ECharts, and Chart.js. Rather than requiring explicit low-level configuration, its compiler infers axis formatting, color scales, temporal parsing, and layout decisions directly from semantic data types and high-level chart mappings. The design separates data specification from chart specification, and includes a Model Context Protocol server that lets AI agents create and validate charts directly within conversational interfaces. In testing, charts generated through Flint scored higher on LLM-judge evaluations than those produced through direct Vega-Lite generation across multiple language models.
