Upgrading agentic coding capabilities with the new Devstral models

Today, we introduce Devstral Medium, as well as an upgrade to Devstral Small. These models are released under the collaboration between Mistral AI and All Hands AI 🙌, with a strong emphasis on generalization to different prompts and agentic scaffolds. 

The new Devstral Small 1.1 is released under the Apache 2.0 license, and is state-of-the-art amongst open models for code agents. Devstral Medium is available through our API, and sets a new point on the cost/performance pareto frontier, surpassing Gemini 2.5 Pro and GPT 4.1 for a quarter of the price.

Devstral Small 1.1

As with the previous version of Devstral Small, we release Devstral Small 1.1 under the Apache 2.0 license. While the architecture remains the same, with only 24B parameters, Devstral Small 1.1 comes with significant improvements over its predecessor:

Enhanced Performance

Devstral Small 1.1 achieves a score of 53.6% on SWE-Bench Verified, and sets a new state-of-the-art for open models without test-time scaling.

Versatility and Generalization

Devstral Small 1.1 excels when paired with OpenHands, and also demonstrates better generalization to different prompts and coding environments. Its versatility is further enhanced by supporting both Mistral function calling and XML formats, making it adaptable to a wide range of applications and agentic scaffolds.

Devstral Medium

Devstral Medium builds upon the strengths of Devstral Small and takes performance to the next level with a score of 61.6% on SWE-Bench Verified. Devstral Medium is available through our public API, and offers exceptional performance at a competitive price point, making it an ideal choice for businesses and developers looking for a high-quality, cost-effective model.

Availability 

Both models are available through our API under the the following names: 

We release Devstral Small 1.1 under the Apache 2.0 license for the community to build on, customize, and accelerate autonomous software development. To try it for yourself, head over to our model card.