Thinking Machines' Inkling 2 Small claims top spot among western open-weight models

Why it matters

Thinking Machines, the startup founded by former OpenAI CTO Mira Murati, has released Inkling 2 Small, a mixture-of-experts model that the company describes as the strongest Western open-weight model available. It performs roughly on par with Google's Gemini 3.8 Flash on the Artificial Analysis Intelligence Index, with the largest gains in agentic tasks, where the model independently executes multi-step workflows. It also leads open-weight models in vision and design benchmarks, including document understanding, visual perception, and user-rated website generation. The improvements carry trade-offs: the model produces far more output tokens and costs several times more per task than its predecessor, though it remains cheaper than competing frontier models. Thinking Machines acknowledges weaknesses, including inefficient communication, suboptimal tool selection on large codebases, no audio support, and occasional overreaction to health topics. The model is currently available through the company's Tinker platform, with weights to be released under an Apache 2.0 license after external safety testing, a more permissive arrangement than licenses used by some competitors. Additional model variants are planned.