OpenAI o1 / o3 Reasoning Systems

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Plain-language summary

Rather than answering immediately, these models generate an extended internal reasoning process and can allocate more or less thinking time to a query. Accuracy on hard reasoning benchmarks improved as more inference compute was spent, establishing test-time compute as a scaling axis distinct from making the model or its training set larger. The reasoning details were released through system cards rather than a formal paper, and the internal chain of thought was kept hidden from users.