GPT-5.1, Now Live in :Harvey:
Announcing GPT-5.1 is now available in Harvey.
Nov 13, 2025
Harvey Team
Today we are making GPT-5.1 available in Harvey.
GPT-5.1 is OpenAI’s newest frontier model, which was trained with an emphasis on dynamic thinking times as well as improvements in formatting, style, and personality. Early access evaluations point to GPT-5.1 providing more detailed and better structured outputs than its predecessor. We expect GPT-5.1 to deliver more complete and structured work products in research, strategic analysis, and drafting.
We’ve also observed improvements in instruction following, which makes GPT-5.1 particularly well-suited for workflows where models need to understand our clients’ exacting standards and their unique style. On our BigLaw Bench evaluation suite, GPT-5.1 achieved the highest score yet for the GPT family of models at 91.8%. This underscores its potential to handle the rigor and nuance of elite legal practice.
“Model performance is improving rapidly. GPT-5.1 shows notable improvements in legal reasoning and instruction-following, which is significant progress in just a few short months since GPT-5's release. With this launch, Harvey clients in professional services are once again at the frontier of model capability.”
Niko Grupen
Head of Applied Research
We’ll be rolling out GPT-5.1 in the model selector to eligible clients in the US and EU over the next 24 hours.