Claude 3.7 Sonnet vs Devstral-2-123B

Claude 3.7 Sonnet

Anthropic

Claude Sonnet 3.7, released by Anthropic in February 2025, is a large language model from the Claude 3 family featuring hybrid reasoning with configurable extended thinking. It supports a 200K token context window, 64K maximum output tokens (128K in beta), and native image understanding. Sonnet 3.7 targets complex coding, mathematics, and scientific reasoning tasks where extended chain-of-thought processing provides meaningful improvements in output quality.

Devstral-2-123B

Mistral AI

Devstral 2, released by Mistral AI on December 9, 2025, is a 123 billion parameter dense transformer model specifically designed for software engineering tasks. It features a 256K token context window and achieved 72.2% on SWE-bench Verified at release, making it a competitive open-weight option for automated coding and agentic development. Devstral 2 targets code generation, multi-file software engineering, and agentic development workflows under a modified MIT license.