Perhaps it would be an officer of the corporation, named in one of the documents on file with the state's Secretary of State or department governing business records. If only the CEO is named, that is the person who has to appear.

I think states usually allow a regular employee of the corporation to appear, though.

Obviously, the small claims court procedures may vary according to jurisdiction, so you'll have to at least check your state's website before running down to the clerk with filings in hand.