Package Registries APIs let you add package registries capabilities without building from scratch. Every entry below is profiled with trust signals — pricing model, authentication requirements, CORS support, rate limits, and live uptime checks — so you can compare options and pick production-safe choices instead of guessing from a link list.
| API | Pricing | Auth | CORS | Health | |
|---|---|---|---|---|---|
| Maven Central Search API Search API for Maven Central components, artifacts, namespaces, and metadata. | Freemium | API Key | Yes | Profile | |
| NuGet V3 API Package registry API for NuGet service index, search, metadata, registration, and downloads. | Freemium | API Key | Yes | Profile | |
| Official MCP Registry API Official Model Context Protocol registry API for discovering public MCP servers and metadata. | Freemium | API Key | Yes | Profile | |
| Open VSX Registry API Open VSX extension registry API for publishing and querying editor extensions. | Freemium | API Key | Yes | Profile | |
| Packagist API Composer package registry API for PHP package metadata and search. | Freemium | API Key | Yes | Profile | |
| PyPI JSON API JSON API for Python package metadata, releases, files, and project information. | Freemium | API Key | Yes | Profile | |
| Terraform Registry API Registry API for Terraform providers, modules, versions, and downloads. | Freemium | API Key | Yes | Profile | |
| npm Downloads API API for npm package download counts and package popularity metrics. | Freemium | API Key | Yes | Profile | |
| npm Registry Public npm package registry API. Search packages, fetch metadata, download stats, and version info for Node.js libraries. No authentication required. | Freemium | No | No | Profile |
Start with pricing and auth: free tiers and no-auth APIs are fastest to prototype with. Then check CORS if your app calls the API from the browser, and health before you commit — a great API that's been down for a week will block your launch. Each profile below shows all of these signals plus rate limits where documented.