Thinking Machines Debuts Inkling 2 Small, Its Strongest Model Yet, With Open Weights Promised Next Week

Thinking Machines Lab introduced Inkling 2 Small, the second generation of its model line and its strongest release so far. The model is a Mixture-of-Experts system with 594 billion total parameters and 17 billion active, supports image inputs, and lets users dial reasoning effort up or down. It scores 31 on the Artificial Analysis Intelligence Index, which the lab calls a big jump over its predecessor.

Availability starts on Tinker, Thinking Machines' own fine-tuning and inference platform, initially with closed weights. The company says it intends to release the full weights under an Apache 2.0 license next week, once external safety testing and red-teaming finish. That staged approach follows the "safe path to open weights" policy the lab published earlier this year.

The pitch is long-horizon agentic work rather than chat. On SWE-bench Pro v2 (Hard) it reports 86.3%, and it scores 81.6% on Vibe Code Bench v1.1 and 72.1% on DeepSWE v1.1, competitive with DeepSeek V4.1 Flash and Kimi K3. The lab also showed it writing a Python PC emulator that boots a real Linux kernel, generating a procedural city simulator, and autonomously training Qwen3.5-4B on Tinker, where a 4.5-hour run costing USD 426 more than doubled a forecasting score.