Metabase vs Shields

Metabase is a self-hosted (or Metabase Cloud) open-source BI tool whose REST API is documented via an interactive OpenAPI/Scalar reference at `/docs/latest/api`; current docs describe generating an `x-api-key` from Admin settings for programmatic access, correcting auth from "None" to "API Key" (the older session-cookie login flow still exists but keyed API access is now the documented path). Its own `MB_DISABLE_CORS_ON_LOCALHOST` config option (default `false`) confirms the server sends CORS headers by default, consistent with cors "yes". The core server is free and open-source to self-host, with paid Pro, Enterprise, and hosted Cloud tiers layered on top.

Shields.io serves status badges as SVG by default from `img.shields.io`, with `.png` requests 301-redirected to a raster-conversion host and a `.json` suffix returning the same badge's label/value/color as plain JSON — all three confirmed live. A live unauthenticated GET returned `Access-Control-Allow-Origin: *` on every format, resolving cors "unknown" to "yes". Free, open-source, and keyless, funded by sponsorships rather than a paid tier.