You're using use strict in both snippets, but none of them compiles, and exactly because you're violating use strict requirements.

Especially

$docs = retrieve('/info/docs');
print $docs{1};
[download]

causes problems because you're retrieving a hash reference ($docs) which you're using as a hash (%docs or $docs{1}) later on. use strict catches this.

Also, checking the result of store() makes sure it's really doing what you expect it to do.