Z.ai: GLM 5.3 FlashX Legal

Z.ai's GLM 5.3 FlashX Legal accepts text, image, and video input, with a context window of 1,048,576 tokens and up to 131,072 tokens per completion. It supports tool calling and a reasoning mode, so it can fit workflows that combine large inputs with external functions. Structured output support is not listed, and the availability of open weights is not stated; teams that depend on either should verify before committing. At $0.37 per million input tokens and $1.25 per million output tokens, it suits workloads that push a lot of material through the context window, such as long documents or video. The name suggests a legal focus, but the available facts do not confirm any legal-specific tuning. It has no independent benchmark coverage yet, so its quality is unproven. Shortlist it for testing alongside benchmarked alternatives rather than as a default choice, and run your own evaluations on representative tasks.