ArcANE asks whether a role-playing language agent adapts a fictional character's behavior to the correct point in the narrative rather than repeating a fixed persona. Its pipeline processes each novel through two LLM streams: one extracts psychologically consequential events and the other produces chapter-level character states. It then proposes intrapersonal or relational axes, reconciles the streams, and segments every axis into phases with chapter ranges, state descriptions, and supporting events. Three LLM critics filter the axes; for the evaluation set, three human annotators reassess validity and a two-of-three majority is required. Each arc generates one scenario and question shared across all phases, with a different reference action and thought for each phase. Probes are In-Scenario when anchored in a real passage, In-World when they invent a situation compatible with the work, and Out-of-World when they transpose the axis to another setting. The latter two references are LLM-authored counterfactual projections, not observed canonical facts. The reported corpus contains 17 novels, 80 characters, 544 arcs, and 4,601 probes: ten novels and 2,545 probes for training; five novels, 25 characters, 205 arcs, and 1,754 probes in the validated evaluation; and two low-popularity novels with seven characters, 31 arcs, and 302 probes without human validation. DeepSeek-V4-Flash/Pro, Qwen3-8B/32B, and ArcANE-8B/32B are compared under Vanilla, Summary, RAG, LifeChoice, TimeCHARA, and Arc context. Arc provides the axis and current phase that also structured the references. DeepSeek-V4-Flash assigns 1-to-100 scores for action fidelity, reasoning fidelity, reasoning-action entailment, and cross-phase trajectory. Arc has the highest Overall score for all six models and in 29 of 30 model-by-novel cells; its Overall values are 59.7 and 62.4 for DeepSeek, 43.1 and 50.1 for Qwen, and 56.9 and 60.4 for ArcANE. Against the strongest alternative context, Overall gains are roughly 2.2 to 8.4 points and grow mainly on scenarios absent from the source. MixedArc, which supplies another character's arc, can fall below Vanilla. ArcHint, containing only the axis label and phase index, remains within 2.6 points of full Arc for untrained models, indicating that much of the prompting effect comes from this compact privileged information. To create ArcANE-8B/32B, SFT uses 45,690 gpt-5.4-mini and claude-sonnet-4-6 responses from the ten training novels; DPO forms 14,671 pairs between an anchor-phase answer and an adjacent-phase answer. A critical inconsistency follows. The appendix says DPO spans 12 novels, 55 characters, and 2,838 probes: 12 and 55 exactly equal the ten-novel/48-character training split plus the two-novel/seven-character low-popularity split, while 2,838 is only nine below their combined 2,847 probes. It is therefore highly likely that The Underdogs and East Lynne enter DPO. For ArcANE-DPO models, this slice cannot serve as a held-out memorization test; it appears held out only from human annotation. The paper releases no DPO identities that could resolve this and also reports 113 DPO axes where the two combined table slices contain 339 arcs. Judge validation is narrower than a blind human comparison: three colleagues see the DeepSeek decision before rating it reasonable or correcting it. A majority approves 61 of 70 cells; on 50 anchored rescoring cells, correlation with the human average is .962 and MAD is 4.7. This checks calibration after exposure to the judge, not independent human agreement. Three additional LLM judges preserve ArcANE-32B-DPO/Arc's first place on 300 cells, but they share the same synthetic references and rubric. The effective generalization unit is only five novels; there are no novel-, character-, or arc-clustered intervals, significance tests, or repeated generations. Code, data, weights, splits, outputs, annotations, and scripts are also not public despite a promise to release them after publication. The defensible contribution is a useful representation of narrative trajectories and evidence that explicitly supplying axis and phase improves agreement with references constructed under the same framework. It does not establish a unique literary interpretation, human personality, internal psychological state, DPO-independent transfer to the low-popularity novels, multi-turn consistency, or safe impersonation.
Research question
Can a role-play agent be evaluated and trained so that it changes its action and reasoning according to the correct phase of a character's narrative arc, especially in situations not written in the work?