China’s Z.AI Co., also known as Zhipu, said it created Ox Alpha, an AI model that has reached the top of online usage charts while offering high performance at no cost. The company confirmed on Wednesday that Ox Alpha is a new iteration of its GLM model series. Z.AI said it will release Ox Alpha’s model weights tonight. The confirmation followed speculation over the model’s origin and development.

OX Alpha, an unnamed large language model available through OpenRouter, identified itself as GLM made by Z.ai after a user supplied text resembling its extracted system prompt. The purported system prompt instructed the model to call itself “ox-alpha” and say it was developed by an undisclosed organization. When shown that instruction as a user message, the model said it would not adopt a false identity and stated that it was GLM from Z.ai. The identity claim came from the model itself after the prompt-injection test, rather than from Z.ai or OpenRouter. A gzip-based normalized compression distance (NCD) comparison also matched OX Alpha most frequently to GLM-5.3 in a reference corpus. The test compared 14 OX Alpha responses against 293 responses from GPT-5.5, Claude Opus 5, Gemini 3.7 Flash, Gemini 3.1 Pro Preview, and GLM-5.3, using a five-nearest-neighbor vote. GLM-5.3 received 7 of 14 matches, followed by Claude Opus 5 with 3, Gemini 3.7 Flash with 2, and GPT-5.5 and Gemini 3.1 Pro Preview with 1 each. GLM-5.3 also led at neighbor settings of 3, 5, 7, and 9. NCD measures how efficiently two texts compress together, with lower scores indicating more shared textual structure.

GLM-5.2 is Z.ai's new open model featuring 744 billion parameters and a 1 million context window, designed for local execution using Unsloth Dynamic GGUFs. It delivers state-of-the-art performance in long-horizon coding, reasoning, and agentic tasks, rivaling Claude 4.8 O.