Microsoft releases Decision-1, a cheap fast model for routing and classification

Microsoft released Microsoft-Decision-1 on 9 October 2026, available now in Microsoft Foundry and through OpenRouter. It is a "decision model": instead of writing text, it takes a fixed set of options and returns a probability for each, for jobs like routing requests, classifying feedback, approving or flagging agent actions and grading AI answers. It is built on Qwen3.5-9B. Input costs $0.042 per million tokens and output is free. Microsoft says it had the highest accuracy in its own 36-benchmark comparison, ran 2.5 times faster than the runner-up, and changed its answer on only 1.3% of reworded or reordered requests. Internally, it says Xbox Research used it to sort more than 10,000 pieces of player feedback into themes at quality competitive with GPT-6 Sol, over 14 times faster and 200 times cheaper. These are Microsoft's own tests. OpenAI's similar Decisions API entered public beta on 6 October.