ZCode and the harness wars

Z.ai shipped ZCode, completing the set: every frontier lab now has a coding agent harness. All three lab-built ones have Issues disabled. None loads another s plugins.

Ox Alpha Was GLM-5.3-Flash: Z.ai Ships MIT Weights After a 62-Trillion-Token Stealth Run

Ox Alpha has a name. Z.ai claimed the cloaked OpenRouter model on August 26 as GLM-5.3-Flash, a 320B-A18B natively multimodal mixture-of-experts model with MIT weights on Hugging Face, and says the entire anonymous preview ran on a cluster of Chinese AI chips. The viral 100 trillion tokens per day figure, though, was never a measurement.

GLM-5.2

Z.ai's GLM-5.2 is the first MIT-licensed model you can self-host that beats GPT-5.5 on long-horizon agentic coding, with a real 1M-token context, at about one-sixth the API cost. What changed, the numbers with their asterisks, and how to run it.

Z.ai GLM-5.1

Z.ai (formerly Zhipu AI) has released GLM-5.1, an open-weight 744 billion parameter Mixture-of-Experts model with 40 billion active parameters. The model immediately took the top spot on SWE-Bench Pro with 58.4, beating GPT-5.4 (57.7) and Claude Opus 4.6 (57.3). Built on DeepSeek Sparse Attention with a 200K context window and 131K maximum output, GLM-5.1 is engineered for sustained autonomous coding agents capable of running plan, execute, test, fix, optimize loops for up to eight hours. The weights are available on Hugging Face under a permissive MIT license for full commercial use.