Nalim Kim
Author directory2026
In-N-Out: A Parameter-Level API Graph Dataset for Tool Agents
Seungkyu Lee | Nalim Kim | Yohan Jo
Transactions of the Association for Computational Linguistics, Volume 14
Seungkyu Lee | Nalim Kim | Yohan Jo
Transactions of the Association for Computational Linguistics, Volume 14
Tool agents—LLM-based systems that interact with external APIs—offer a way to execute real-world tasks. However, as tasks become increasingly complex, these agents struggle to identify and call the correct APIs in the proper order. To tackle this problem, we investigate converting API documentation into a structured API graph that captures API dependencies and leveraging it for multi-tool queries that require compositional API calls. To support this, we introduce In-N-Out, the first expert-annotated dataset of API graphs built from two real-world API benchmarks and their documentation. Using In-N-Out significantly improves performance on both tool retrieval and multi-tool query generation, nearly doubling that of LLMs using documentation alone. Moreover, graphs generated by models fine-tuned on In-N-Out close 90% of this gap, showing that our dataset helps models learn to comprehend API documentation and parameter relationships. Our findings highlight the promise of using explicit API graphs for tool agents and the utility of In-N-Out as a valuable resource. We release our dataset and code at https://github.com/holi-lab/In-N-Out-API-Graph.
ArcANE: Do Role-Playing Language Agents Stay in Character at the Right Time?
Woojung Song | Nalim Kim | Sangjun Song | Chaewon Heo | Jongwon Lim | Yohan Jo
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Woojung Song | Nalim Kim | Sangjun Song | Chaewon Heo | Jongwon Lim | Yohan Jo
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Role-playing language agents (RPLAs) simulate specific characters and personas across applications such as entertainment, companionship, interactive storytelling, and education. Faithful role-play requires more than producing plausible, in-character responses: as a character’s values and behavior change over a narrative, an RPLA should reflect the character’s state at the relevant stage. However, existing benchmarks largely treat characters as fixed personas or test only what they know at a given point in the narrative. We introduce **ArcANE** (Arc-Aware Narrative Evaluation), a benchmark for evaluating whether an RPLA follows a character’s development across a narrative. **ArcANE** first builds an Arc that maps how a character’s values, motivations, or relationships change over the story. The benchmark then scores how well an RPLA’s responses fit the corresponding stages of the Arc, covering three distinct scenario types: scenes from the novel, new situations within its world, and situations outside that world. We evaluate six models under six ways of providing narrative context. In every model, using the Arc up to the queried chapter yields the best performance, outperforming the strongest non-Arc context by 2.2–8.4 points. These results suggest that faithful role-play requires evolving character states and tracking their trajectory, rather than merely retrieving relevant episodic evidence.