Microsoft Decision-1: 9B Qwen Model Launch Explained

Microsoft introduced Microsoft-Decision-1 on October 9, 2026, a specialized model that scores predefined answer choices rather than generating text. Built by post-training Alibaba’s 9-billion-parameter open-weight Qwen3.5-9B model, it returns calibrated probability scores for tasks including routing, classification, prioritization, verification and workflow control. It supports text inputs of up to 32,000 tokens but does not provide written explanations or process images, audio or video. Microsoft said future versions will be rebased on Microsoft AI and OpenAI models. The model launched in public preview through Microsoft Foundry and became available on OpenRouter as microsoft/microsoft-decision-1. Its weights are not distributed, limiting use to hosted APIs. OpenRouter and secondary reports list pricing at $0.042 per million input tokens with no output-token charge. Microsoft said Decision-1 achieved 83.5% accuracy across 36 benchmarks containing roughly 150,000 held-out questions, and reported approximately 35 times lower P50 latency than GPT-6 Sol and 4.5 times faster performance than Quyet-1.0-Large; those results have not been independently reproduced. Microsoft also reported 98.7% perturbation stability and said it is testing the model internally for incident response, quality control and scientific discovery. Xbox Research reportedly used it to categorize more than 10,000 feedback items into predefined themes.