Mistral Small 4 released with 256k context, and Leanstral for Lean 4 proofs

We released Mistral Small 4 (mistral-small-2603), a hybrid model unifying instruct, reasoning, and coding in a single multimodal model with a 256k context window. (model)
We released Leanstral (labs-leanstral-2603), our first open-source code agent designed for Lean 4 formal proof engineering. (model)