KuaiRP Series Role-playing Models Technical Report
Paper: arXiv:2609.11127 Categories: cs.AI, cs.CL Authors: Yipeng Wang, Ziwei Zhang, Jiahui Zhang, Qi Gan, Kai Sheng Published: 2026-09-13
Overview
This paper introduces the complete technical solution for the KuaiRP series of role-playing models. The authors aim to achieve four core objectives for a dedicated role-playing model:
- Simplified prompt engineering
- Highly stable output quality
- Built-in domain world knowledge
- High-efficiency deployment with a small parameter size
- Match current state-of-the-art proprietary models in role-playing fidelity within the target domains
- Successfully recover general agent capabilities
- Maintain extremely low deployment costs
The Core Challenge
Effectively injecting deep domain knowledge often leads to severe catastrophic forgetting of the model's general agent capabilities. To overcome this trade-off, the authors propose a multi-stage training pipeline.
Training Pipeline
1. SFT stage: A standardized character template is designed, and an SFT data pipeline is constructed based on user behavior simulation and reverse profile filtering. 2. Reinforcement Learning stage: A rule-based composite reward function eliminates common degradation phenomena such as length expansion and repetitive generation. 3. Self-distillation stage: To recover general capabilities compromised during SFT and RL, the authors propose a novel self-distillation paradigm using Two-stage On-Policy Distillation (OPD) equipped with Cumulative-Divergence Decay (CDD). The domain-adapted model serves as the teacher and the original base model as the student, balancing deep domain knowledge injection with the preservation of general agent capabilities.
Results
Experimental results demonstrate that the KuaiRP models: