Who's behind the mystery model Ox Alpha? On Polymarket, the guessing game has shifted hard toward Zhipu. Z.ai is now above 90%, while Google sits second at around 5%. Ox Alpha is the anonymous reasoning model that just appeared on OpenRouter, built for coding and long-running agent tasks.
The strongest clue comes from the backend. Developers deliberately sent malformed parameters to the Ox Alpha endpoint on OpenCode, and the server spat back com.wd.paas.api.domain.v4.chat.ChatCompletionRequest — a class name whose paas/v4/chat path maps directly onto Z.ai's official API. Send it an invalid role and Ox Alpha returns 1214 Incorrect role information, the same error Zhipu's own hosted GLM produces. Put the same GLM weights on DeepInfra, and the error format changes.
The model's fingerprint matches too. A public forensics run sent more than 600 requests and roughly 13.5 million input tokens through it; all 44 tokenizer tests lined up with the GLM-5 generation.