---
title: API Documentation
weight: 400
---

Crossplane packages offer API types in a cluster by installing CRDs or XRDs.
Packages that are pushed to `xpkg.upbound.io` have auto-generated documentation
for their API types on the [Upbound Marketplace]. You can access documentation
for the most recent release of any package by navigating to
`https://marketplace.upbound.io/{provider|configuration}/<org>/<repo>`.

Crossplane repositories that do not contain providers or configurations, but do
publish CRDs, are served on [doc.crds.dev]. For instance, the
[crossplane/crossplane] repository.

<!-- Named Links -->

[Upbound Marketplace]: https://marketplace.upbound.io
[doc.crds.dev]: https://doc.crds.dev/
[crossplane/crossplane]: https://doc.crds.dev/github.com/crossplane/crossplane