How to get `package.json` link from the registry – by using a shell script?

Hello,
I want to extend a Zsh plugin manager (Zplugin) with support for keeping the plugins inside the registry. Specifically, a plugin is installed by preceding it with a list of so called ice-modifiers, e.g.:

# fzy
zplugin ice wait"1" lucid as"program" pick"$ZPFX/bin/fzy*" \
    atclone"cp contrib/fzy-* $ZPFX/bin/" \
    make"!PREFIX=$ZPFX install"
zplugin light jhawthorn/fzy

The point is that by storing a Zsh plugin definition in the registry it would be possible to store the ice-lists in the … package.json, probably, in some custom field. This way the user could simply zplugin registry fzy and the predefined, standard ice-list would be pulled.

However, how to get the following data from the registry – by using a shell script? I.e.:

  • How to get package.json?
  • How to get the link to the original repository of the project?

UPDATE: I can see that getting the package.json (I’m not sure if it’s exactly that, rather not?) is as easy as curl https://registry.npmjs.org/./PACKAGE-NAME, and that the output can be then passed to e.g.: jq.

I wonder if the registry can also store tarballs? Because it seems to, the returned json contains e.g.: "tarball": "https://registry.npmjs.org/remark/-/remark-11.0.1.tgz",

Can a different format than JSON be requested?