Thinking Machines introduced Inkling 2 Small on Nov. 5, 2026, making its second model generation available through Tinker for fine-tuning and inference. The company’s launch announcement also offers access through Tinker Playground.
Hosted access comes first. Thinking Machines is initially keeping the model’s weights closed and intends to release them under an Apache 2.0 license the following week, after external safety testing and red-teaming. Its release plan also ties downloadable checkpoints to the release of the weights.
According to Thinking Machines, Inkling 2 Small is a mixture-of-experts model with 594 billion total parameters and 17 billion active parameters. It supports image inputs and variable effort.
The company reports a score of 31 on the Artificial Analysis Intelligence Index, which it describes as far above its previous models’ scores. Thinking Machines associates that improvement with gains in agentic coding, vision, knowledge work and reasoning.
For its coding training, the company describes using reinforcement learning on hundreds of thousands of long-horizon tasks across multiple agent harnesses and context-compaction strategies. It also says some training tasks evaluated , rather than relying on whether its code passed tests alone.
