Is there a specific explanation about how this is better or different than vega itself? https://vega.github.io/vega/docs/specification/
My understanding is that Vega was already an expressive DSL for visualizations and its probably already well spread through LLM training data.
Vega was a high-level language in the past for human, but now they can be a bit too low-level for AI agents! AI agents have to write a lot of low-level params just to make charts looking good, and the result is that programs are hard to write reliably for AI agents.
Flint is a higher-level abstraction, with simpler much shorter spec, and the compiler derives low-level decisions so that charts are looking good.
So: flint lets agent write short program that achieving good looking charts that had to be done with lengthy program in the past.