A couple of questions:
Do you mean a feature that could be included by the problem author to require parentheses for function calls, or something that can be turned on globally on a class-by-class basis (or something else)? (I'm not sure doing it on a problem-by-problem basis is a good idea, as I think it would be confusing to students to have the syntax change from one to the next.)
Can you give some examples of the ambiguities and messages that you have in mind?
Features & Development
request option to require careful notation in answers
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