why is the tool using tox internals via include and not the public API?

[zoff99]

c-toxcore/testing/decrypt_save.c

Line 4 in d10c966

#include "../toxencryptsave/toxencryptsave.h"

like this the tool can not be used as-is standalone with toxcore installed system wide

[iphydf]

It's just like all other tools and things in the testing/ directory, or anything in the toxcore source tree. These are not "toxins", they are testing utilities inside toxcore. Feel free to make a PR into the toxins repo to make this a public tool to be built against a system toxcore.