# STAC Lens

> See the shape of your STAC data — structure, time, and space as one coordinated view. A free, open-source, browser-only viewer and health checker for STAC (SpatioTemporal Asset Catalog) catalogs and APIs: paste a catalog URL and see how the publisher organized it, what it covers in time and space, where its metadata contradicts itself or the specification, and what its API really does when asked.

STAC Lens runs at https://staclens.com and has no backend: every request goes from the visitor's browser to the catalog being explored. It is not a replacement for STAC Browser (which reads a catalog faithfully, one object per page); it is a lens on a catalog's shape, health and distance from the specification. "Health" is a list of findings traceable to rules in the STAC specification, its best practices, stac-check and the STAC API specification — never a score, and never a rule this project invented. Source: https://github.com/rednotfound/stac-lens (Apache-2.0).

## Docs

- [About STAC Lens](https://staclens.com/about.md): what it is, who it is for, how it differs from STAC Browser, principles, vocabulary
- [Health rules](https://staclens.com/health-rules.md): every check the app performs or could perform, with source, severity tier and status; rule ids such as C-04 are citable anchors
- [Public STAC catalogs](https://staclens.com/catalogs.md): the verified list of public STAC catalogs and APIs on the landing page, with tags (entries that currently fail are marked)
- [Deploying](https://staclens.com/deploy.md): self-hosting on any static host, Docker, sub-paths

## Source

- [README](https://github.com/rednotfound/stac-lens/blob/main/README.md): overview, STAC support matrix, getting started
- [Design log](https://github.com/rednotfound/stac-lens/blob/main/docs/DESIGN.md): research notes, decisions and post-mortems, including observed behavior of real STAC servers
- [Architecture](https://github.com/rednotfound/stac-lens/blob/main/docs/ARCHITECTURE.md): the code as it is
- [Issues](https://github.com/rednotfound/stac-lens/issues): catalogs that render oddly, disagreements about what health should mean

## Optional

- [关于 STAC Lens（中文）](https://staclens.com/zh/about.md): the About page in Chinese