Fix error checking with asserts and fix typos
Fix error checking with asserts and fix typos

fabianvf/scrapi,mehanig/scrapi,erinspace/scrapi,felliott/scrapi,erinspace/scrapi,felliott/scrapi,fabianvf/scrapi,CenterForOpenScience/scrapi,mehanig/scrapi,CenterForOpenScience/scrapi