> For the complete documentation index, see [llms.txt](https://docs.geoprismregistry.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.geoprismregistry.com/readme/current/external-system-integration/4.1-available-apis.md).

# 4.1. Available APIs

The GeoPrism Registry developer REST API has the functionality to access data with external system identifiers. See the [documentation](https://api.geoprismregistry.com) for more details.