Dec 10, 2025 10:55:00

Mistral AI releases Devstral 2, a small, high-performance open AI model, and Mistral Vibe CLI, a vibration coding tool.

AI development company

Mistral AI has released two open-source AI models, Devstral 2 and Devstral Small 2 , specializing in coding. Devstral 2 is characterized by its compact size and high performance, and is said to be seven times more cost-effective than Claude Sonnet. Mistral also released a CLI tool for vibe coding, Mistral Vibe CLI .

Introducing: Devstral 2 and Mistral Vibe CLI. | Mistral AI
https://mistral.ai/news/devstral-2-vibe-cli

Devstral 2 is an AI model with 123 billion (123B) parameters and 256,000 (256K) context windows, and achieved a score of 72.2% on the SWE-bench Verified benchmark, which measures AI coding performance, comparable to larger models. Devstral Small 2 is a small model with 24 billion (24B) parameters that can be easily run on a home PC, and achieved a score of 68.0% on SWE-bench Verified, far exceeding models of the same size.

The graph below shows the size of the model on the horizontal axis and the SWE-bench Verified score on the vertical axis. It clearly shows that Devstral 2 and Devstral Small 2 are small and high-performance.

The performance of 'Devstral 2' compared with 'DeepSeek V3.2' and 'Claude Sonnet 4.5' is shown below. As a result of human evaluation, Devstral 2 recorded a 42.8% win rate against DeepSeek V3.2. On the other hand, in a showdown with the closed-source model Claude Sonnet 4.5, the win rate was 21.4% and the loss rate was 53.1%. Mistral AI claims that Devstral 2's performance can be 'seven times more cost-effective than Claude Sonnet in real-world tasks.'

Devstral 2 is available under the Modified MIT License , and Devstral Small 2 is available under the Apache 2.0 License at the following links. Devstral Small 2 can run on a home PC, but Devstral 2 requires at least four H100s.

mistralai/Devstral-2-123B-Instruct-2512 · Hugging Face
https://huggingface.co/mistralai/Devstral-2-123B-Instruct-2512

mistralai/Devstral-Small-2-24B-Instruct-2512 · Hugging Face
https://huggingface.co/mistralai/Devstral-Small-2-24B-Instruct-2512

In addition, the company has released 'Mistral Vibe CLI,' a CLI tool for vibe coding using the Devstral series. Mistral Vibe CLI is available as a Zed extension , and the source code is available under the Apache 2.0 License.

Mistral Vibe CLI is an open-source command-line coding assistant powered by Devstral.
It explores, modifies, and executes changes across your codebase using natural language. Also under Apache 2.0.
Install via: uv tool install mistral-vibe pic.twitter.com/wcJWmSWt3O

— Mistral AI (@MistralAI) December 9, 2025

Devstral 2 and Devstral Small 2 are also available via Mistral AI's API and are free at the time of writing. After the free period ends, the fee per million tokens will be $0.40 (approximately ¥62.70) for input and $2 (approximately ¥313.50) for output. Devstral Small 2 will be $0.10 (approximately ¥15.70) for input and $0.30 (approximately ¥470) for output.