We use essential cookies to make our site work. With your consent, we may also use non-essential cookies to improve user experience and analyze website traffic…
mistralai/Devstral-Small-2507 cover image
featured

mistralai/Devstral-Small-2507

Devstral is an agentic LLM for software engineering tasks, making it a great choice for software engineering agents.

Devstral is an agentic LLM for software engineering tasks, making it a great choice for software engineering agents.

Public
$0.07/$0.28 in/out Mtoken
fp8
128,000
Function
mistralai/Devstral-Small-2507 cover image

Devstral-Small-2507

Ask me anything

0.00s

Devstral Small 1.1

Devstral is an agentic LLM for software engineering tasks built under a collaboration between Mistral AI and All Hands AI 🙌. Devstral excels at using tools to explore codebases, editing multiple files and power software engineering agents. The model achieves remarkable performance on SWE-bench which positionates it as the #1 open source model on this benchmark.

It is finetuned from Mistral-Small-3.1, therefore it has a long context window of up to 128k tokens. As a coding agent, Devstral is text-only and before fine-tuning from Mistral-Small-3.1 the vision encoder was removed.

For enterprises requiring specialized capabilities (increased context, domain-specific knowledge, etc.), we will release commercial models beyond what Mistral AI contributes to the community.

Learn more about Devstral in our blog post.

Updates compared to Devstral Small 1.0:

  • Improved performance, please refer to the benchmark results.
  • Devstral Small 1.1 is still great when paired with OpenHands. This new version also generalizes better to other prompts and coding environments.
  • Supports Mistral's function calling format.

Key Features:

  • Agentic coding: Devstral is designed to excel at agentic coding tasks, making it a great choice for software engineering agents.
  • lightweight: with its compact size of just 24 billion parameters, Devstral is light enough to run on a single RTX 4090 or a Mac with 32GB RAM, making it an appropriate model for local deployment and on-device use.
  • Apache 2.0 License: Open license allowing usage and modification for both commercial and non-commercial purposes.
  • Context Window: A 128k context window.
  • Tokenizer: Utilizes a Tekken tokenizer with a 131k vocabulary size.

Benchmark Results

SWE-Bench

Devstral Small 1.1 achieves a score of 53.6% on SWE-Bench Verified, outperforming Devstral Small 1.0 by +6,8% and the second best state of the art model by +11.4%.

ModelAgentic ScaffoldSWE-Bench Verified (%)
Devstral Small 1.1OpenHands Scaffold53.6
Devstral Small 1.0OpenHands Scaffold46.8
GPT-4.1-miniOpenAI Scaffold23.6
Claude 3.5 HaikuAnthropic Scaffold40.6
SWE-smith-LM 32BSWE-agent Scaffold40.2
Skywork SWEOpenHands Scaffold38.0
DeepSWER2E-Gym Scaffold42.2

When evaluated under the same test scaffold (OpenHands, provided by All Hands AI 🙌), Devstral exceeds far larger models such as Deepseek-V3-0324 and Qwen3 232B-A22B.