Mistral AI and All Hands AI Launch Devstral, Agentic Coding LLM

French AI startup Mistral AI, in collaboration with All Hands AI, has unveiled a new open-source AI model for coding assistance called Devstral. Described as an “agentic” large language model, Devstral is specifically designed to tackle multi-step software engineering tasks across entire projects (not just single-function completions). This broad approach enables it to address real GitHub issues with exceptional proficiency. In fact, Devstral scored 46.8% on a benchmark of 500 real-world GitHub issues (SWE-Bench Verified), outperforming the previous best open-source models by about 6 percentage points. That makes it the new state-of-the-art among open models for coding problems.

An open model that’s lightweight and self-hostable

Devstral is also notable for its accessibility and openness. The model is efficient enough to run on a single NVIDIA RTX 4090 GPU or even a Mac with 32 GB of RAM, meaning developers and companies can self-host it without needing a giant supercomputer. It’s released under an Apache 2.0 open-source license, allowing free use (including commercially) and easy integration. Devstral is available starting now — developers can access it via Mistral’s API or download it to run locally. The model is designed to work with existing “agent” frameworks (such as OpenHands, which provides an automated testing interface), enabling it to explore a codebase, edit multiple files, and run code iteratively during problem-solving. Mistral had previously dipped into coding models with a prototype called Codestral, but that model’s license restricted commercial use; Devstral, by contrast, delivers high performance with a permissive license and modest hardware requirements. It provides a compelling open alternative to proprietary coding assistants, empowering the open-source community and businesses to deploy advanced AI coding help on their own terms.