GLM-5 is unbelievable (Opus for 20% the cost??)

GLM-5, a new open-weight AI model from Chinese lab Zhipu AI, delivers performance comparable to Claude Opus 4.5 and Codex 5.2 at roughly 20% of the cost. With 744 billion parameters (40B active via mixture-of-experts), it excels at long-running agentic tasks, successfully completing hour-long code migrations that previously required closed-weight models. The model achieves the lowest hallucination rate on benchmarks to date, costs $3 per million output tokens versus $15-18 for top closed models, and is MIT-licensed without usage restrictions. While lacking multimodal image support, it demonstrates strong capabilities in code refactoring, UI generation, and extended autonomous work sessions.