ChatNPC: Towards Immersive Video Game Experience through Naturalistic and Emotive Dialogue Agent

ACL ARR 2026 January Submission1908 Authors

Keywords: conversational modeling; game companion; non-player character; sentinel agent; user immersion

Abstract: We present ChatNPC, a game companion that dynamically personalizes its responses based on players' emotional shifts in real-time to enhance user immersion. The model integrates sequential data, leveraging the dynamic nature of streams to benefit from player information, spoken lines, and in-game context. We leverage recent progress in LLMs' tool-calling capabilities to extract vital information from memory and recognize potential constraints for accurate reasoning, thereby tackling the complexity of NPC conversation scenarios. The task is divided into 1, a novel game sentinel agent (SeGent); 2, a memory capability; and 3, a chat planning tool for reasoning instantiation. The approach benefits from a lightweight game-template as an information framework, with relevant details and a thorough reasoning layout. We conduct extensive experiments on a newly developed game dataset for in-game context NPC dialogue and demonstrate that ChatNPC sequentially captures players' emotional shifts over time; responses are more naturalistic and human-like with appropriate conversational cues, pauses, and sighs; and utterances remain faithful to the dynamics of in-game context and player actions, supporting narrative continuity.

Paper Type: Long

Research Area: Dialogue and Interactive Systems

Research Area Keywords: spoken dialogue systems; human-in-the-loop; applications; conversational modeling;

Contribution Types: Reproduction study

Languages Studied: English

Submission Number: 1908