GLM-5.3-FlashX-Legal

GLM-5.3-FlashX-Legal (GLM-Legal) is Z.ai's legal-domain variant of GLM-5.3-FlashX, the fast serving tier of GLM-5.3-Flash. It adds legal-domain mid-training and reinforcement-learning post-training across tens of thousands of environments modeled on real legal workflows (legal research, contract review, evidence analysis, document drafting), and is designed to run in agent harnesses with legal-data and Word drafting/revision MCP services. It accepts text, image, and video input with text output, has a 1M-token context window and 128K max output, and runs with always-on thinking (reasoning effort low, high, or max). Z.ai reports a 19.2% all-pass rate on Harvey's Legal Agent Benchmark (LAB), 12.5 points above the base model, independently evaluated by Vals. Announced 2026-10-12; Z.ai lists API pricing at $0.37 input, $0.075 cached input, and $1.25 output per million tokens (API access by application for enterprise customers), and the model is also listed on OpenRouter as z-ai/glm-5.3-flashx-legal.