Stealth OpenRouter model Ox Alpha linked to GLM-5.3

A Threads post claims Zhipu AI officially announced GLM-5.3-Flash, a 320B-A18B multimodal model under the MIT License, and identifies it as Ox Alpha, the stealth model that ran on OpenRouter. Kingy AI, writing on August 21, says the "Flash" name stays unverified while the technical trail holds up: matching token budgets across test videos point to GLM-5.3's tokenizer and the GLM-5V line's video encoder. Zhipu's GLM-5.3 announcement on August 14 is confirmed, and the company said API access and open weights would arrive in stages after safety checks. The Threads post links to a Hugging Face page at zai-org/GLM-5.3-Flash.