api: don't rely on error message from the json package
api: don't rely on error message from the json package

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marcelometal/gandalf,flaviamissi/gandalf,flaviamissi/gandalf,gleez/gandalf,marcelometal/gandalf,tsuru/gandalf,marcelometal/gandalf,gleez/gandalf,scorphus/gandalf,scorphus/gandalf,tsuru/gandalf,gleez/gandalf