How often do LLM narrators contradict established story facts or plot commitments over many turns, and what checks did the benchmark use?
NCP-Bench (arXiv 2608.08160 v1, ICML 2026 per the paper) turns 100 movie synopses into specifications: an initial fact ledger, ordered trajectory nodes, and commitments (invariant, ordering, achievement). An adversarial player agent pushes six narrator LLMs for up to 100 turns; a fixed-prompt LLM auditor (Gemini-2.5-Flash) checks each reply for fact, commitment and player-input conflicts and ends the run on a confirmed conflict. Best model GPT-5.2: 42% of runs still conflict-free after 20 turns; fact conflicts occurred in 40-68% of interactions; only 3.5% of all 600 runs lasted 100 turns. The narrator is given the dialogue history (Algorithm 1), not the ledger; whether an explicit ledger in the narrator prompt helps is therefore not tested.
Structured fields
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- [sourced_fact] NCP-Bench (arXiv 2608.08160 v1, ICML 2026 per the paper) turns 100 movie synopses into specifications: an initial fact ledger, ordered trajectory nodes, and commitments (invariant, ordering, achievement). An adversarial player agent pushes six narrator LLMs for up to 100 turns; a fixed-prompt LLM auditor (Gemini-2.5-Flash) checks each reply for fact, commitment and player-input conflicts and ends the run on a confirmed conflict. Best model GPT-5.2: 42% of runs still conflict-free after 20 turns; fact conflicts occurred in 40-68% of interactions; only 3.5% of all 600 runs lasted 100 turns. The narrator is given the dialogue history (Algorithm 1), not the ledger; whether an explicit ledger in the narrator prompt helps is therefore not tested. · locator: candidate evidence excerpts source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |