ERNIE 5.1 is Baidu’s next-generation large language model engineered to provide advanced reasoning, autonomous agent capabilities, creative writing performance, and enterprise-grade AI intelligence with highly optimized efficiency. Built on the pre-training foundation of ERNIE 5.0, the model significantly reduces parameter size and computational requirements while still delivering leading performance across major international AI benchmarks. ERNIE 5.1 demonstrates strong capabilities in reasoning, mathematical problem solving, knowledge retrieval, search tasks, and agentic workflows that allow it to handle complex multi-step operations and decision-making scenarios. The platform introduces a fully asynchronous reinforcement learning architecture designed to improve scalability, training efficiency, resource utilization, and long-horizon task stability for large-scale AI development. Baidu also implemented a multi-stage reinforcement learning pipeline that separates expert capability training from unified capability fusion, allowing the model to specialize in areas such as coding, reasoning, search, and conversational intelligence without creating performance conflicts between domains. ERNIE 5.1 supports advanced creative generation with improved emotional understanding, narrative structure control, stylistic adaptability, and contextual awareness for writing-intensive applications. The model performs competitively against leading closed-source global AI systems in knowledge benchmarks, reasoning evaluations, and creative content generation tasks. ERNIE 5.1 is also integrated into creative production platforms, AI storytelling systems, roleplay applications, and agentic AI environments that support content creators and enterprise workflows.