{"data":{"slug":"flint-chart","name":"Flint","tagline":"MIT chart language and MCP server that turns short specs into polished charts","category":"libraries","categoryName":"Libraries","url":"https://microsoft.github.io/flint-chart/","github":"https://github.com/microsoft/flint-chart","pricing":"open-source","hook":"Flint is a chart spec from Microsoft built for agents: you (or a model) describe what each field means and which chart you want, and Flint works out scales, axes, spacing, labels and layout, then compiles to Vega-Lite, ECharts, Chart.js, Plotly or a native Excel chart.","whatsGood":"MIT (microsoft/flint-chart), release 0.5.1 (2026-08-14). 70+ semantic types (Rank, Price, Country and so on) drive layout decisions that agents usually get wrong by hand. A formal theme spec applies a house style across a whole chart library, with presets in the style of the NYT, Economist, Swiss and McKinsey. npm install flint-chart for the library; npx -y flint-chart-mcp runs a local MCP server that lets an agent pick a template, validate it and open an interactive chart view. Backed by an arXiv paper. ★~4.4k.","theCatch":"Pre-1.0, so the spec can still move. The Python package is not released yet; the port in the repo is a source-only preview. The README pushes a hosted MCP endpoint first; for private or large data, run the local server instead. It is a layer on top of existing chart libraries, so you still ship Vega-Lite, ECharts or Plotly to render.","verdict":"A sensible middle layer when agents draw your charts — pin the version while it is pre-1.0.","addedAt":"2026-10-19","featured":false,"domain":"Libraries","subSpecialty":"Libraries","subcategory":"Libraries","tags":["mcp","sdk","self-host","permissive","active","young-repo"],"capabilities":["mcp"],"surfaces":["MCP","Self-host"],"ecosystem":["Node.js"],"licenseModel":"OSS/MIT","githubStars":4379,"starsPerWeek":192,"access":"free","archived":false,"repo":{"createdAt":"2026-05-13","pushedAt":"2026-10-18","license":"MIT","archived":false,"checkedAt":"2026-10-19"}},"related":[{"slug":"hono","name":"Hono","tagline":"Tiny TypeScript web framework that runs on every runtime"},{"slug":"phaser","name":"Phaser","tagline":"MIT HTML5 2D game framework with scenes, physics, and tilemaps"},{"slug":"pixijs","name":"PixiJS","tagline":"MIT 2D WebGPU/WebGL renderer, not a game engine"},{"slug":"babylonjs","name":"Babylon.js","tagline":"Apache-2.0 3D engine for the web, now on v9"},{"slug":"playcanvas","name":"PlayCanvas","tagline":"MIT WebGL2/WebGPU engine plus an optional hosted Editor"}],"links":{"self":"/api/gems/flint-chart","html":"/gems/flint-chart","markdown":"/gems/flint-chart.md","category":"/api/gems?category=libraries","categoryPage":"/stacks/libraries"}}