This is useful in having both a limited footprint from a repo, while also the ability to update.

I use this to keep a library of AI skills up-to-date, without having to copy them manually:

$ cd ~/.agents/
$ git clone --filter=blob:none --sparse https://github.com/anthropics/skills anthropics-skills
$ cd anthropics-skills
$ git sparse-checkout set skills/frontend-design
$ ln -s ~/.agents/anthropics-skills/skills/frontend-design ~/.agents/skills/frontend-design

• --filter=blob:none
  Tells Git to clone without downloading any file contents (blobs) upfront. You get the full commit history and directory tree metadata, but actual file data is fetched lazily — only when you check out or access a file. This makes the initial clone much faster for large repos.
• --sparse
  Enables sparse checkout mode, which means Git will only populate your working directory with a subset of files instead of everything in the repo.
• git sparse-checkout set skills/frontend-design
  Configures which paths to materialize in the working directory. After this command, only the skills/frontend-design/ directory will appear on disk. Everything else exists in the Git object store but won’t be written to your filesystem.

Later on, git pull behaves like a normal pull but scoped to what has been materialized.