Upstage unveils 'Solar Pro 4,' becomes first Korean model listed on global developer platforms

[Financial News] Upstage, which is participating in the government’s independent Artificial Intelligence (AI) foundation model project, said on the 14th that it had unveiled Solar Pro 4, a Large Language Model (LLM) with improved reasoning and agent capabilities.
Solar Pro 4 is designed to strengthen reasoning and agent capabilities compared with its predecessor. Rather than focusing on benchmark scores for one-off answers, it is optimized for real-world workflows such as document understanding, information extraction, long-context reasoning, and continuous decision-making.
Shortly after its release, Solar Pro 4 became the first Korean model to be listed on Hermes Agent, an AI agent developed by Nous Research in the United States, and on OpenRouter, an application programming interface (API) routing platform.
Upstage is the first Korean company to be listed as an official provider among U.S. big tech firms such as OpenAI, Anthropic, Google, and NVIDIA, as well as major Chinese companies including DeepSeek, Moonshot AI, and MiniMax Group Inc.
Three days after being listed on OpenRouter, cumulative token usage for Solar Pro 4 surpassed 8 billion tokens.
It also became the first Korean model to enter the Agent Arena leaderboard, which compares the agent performance of major global models, and was rated at a level similar to NVIDIA Nemotron 3 Ultra.
In performance evaluations, the model scored 57 on TerminalBench, which measures terminal task completion ability, a 4.8-fold increase from its predecessor. It also scored 23 on τ3-Bench, which assesses tool-use capability, marking a 2.6-fold improvement.
In the Artificial Analysis Long Context Reasoning (AA-LCR) benchmark, it scored 71, more than 2.3 times better than the previous model. Based on Artificial Analysis’s overall evaluation, it received 42 points, more than tripling its predecessor’s performance.
Upstage CEO Sung Kim said, "Being the first Korean model to be listed on a global developer platform is proof that our AI technology works in real-world settings," adding, "We will continue to build more practical AI based on technology proven in the field."


[email protected] Juwon Gwon Reporter