Interactional language – language that regulates communication rather than conveying truth-conditional content – is a core feature of human-human interaction, yet its role in human-computer dialogue remains underexplored. This study examines how users perceive the interactional marker “huh?” in conversations with conversational user interfaces, focusing on its naturalness across two contexts: other-initiated repair, which manages turn-taking, and requests for confirmation, which manage common ground. Using storyboards in a naturalness judgment task with 200 native English speakers, we observed a functional asymmetry. In other-initiated repair, interactional and non-interactional forms were rated similarly, with a slight, non-significant advantage for non-interactional forms, leaving user tolerance of interactional markers inconclusive. In contrast, interactional forms in requests for confirmation were rated significantly less natural, reflecting users’ expectation of epistemic alignment that they do not intuitively attribute to machines. These results challenge the Computers as Social Actors paradigm, showing that users apply context-sensitive social scripts in human-computer interaction rather than indiscriminately mapping human-human norms. Interactional language thus provides a critical diagnostic for assessing conversational user interfaces’ interactional competence.