Mistral Medium 3.5 Launches: 128B Dense Open-Weight Model with 256K Context, Modified MIT License

Mistral AI·high signal

Mistral AI released Mistral Medium 3.5, a 128B dense parameter model with 256K context window — their first flagship merged model combining instruction following, reasoning, and coding. Available as open weights under modified MIT (commercial use requires license), self-hostable on as few as four H100/H200 GPUs. Launched alongside 'Vibe' remote agents and Work Mode in Le Chat. Reddit reaction massive: 498 upvotes on r/LocalLLaMA with 294 comments, plus multiple cross-posts across r/singularity (150 upvotes).