Research review / models

Inkling 2 Small Launches With Closed Weights and a Promise to Open Them Next Week

Thinking Machines released Inkling 2 Small on November 5, a 594B-parameter Mixture-of-Experts model with 17B active, through its Tinker service. Apache 2.0 weights are promised after outside safety testing. In its own coding table it is not the top model in any row.

By Sandeep Belgavi · Published 2026-11-07

On November 5, 2026, Thinking Machines introduced Inkling 2 Small, its second model generation. It is a Mixture-of-Experts model "with 594B total parameters, 17B active", with image input and adjustable effort. It is available now for sampling and fine-tuning through Tinker, but with closed weights. The company says it intends "to make the full weights available under an Apache 2.0 license next week after the completion of external safety testing and red-teaming." Checkpoints fine-tuned on Tinker become downloadable when that happens.

What the company reports

Thinking Machines cites a score of 31 on the Artificial Analysis Intelligence Index and publishes a large table of evaluations, all run at effort 0.99 with a 1M-token trajectory limit. Its own comparison is more candid than most launch pages, because the model often does not win:

  • FrontierCode v2.0: 25.4 percent, against 28.5 percent for DeepSeek-V4.1-Flash-1017.
  • DeepSWE v1.1: 72.1 percent, against 77.0 percent for the same DeepSeek model and 68.5 percent for Kimi K3.
  • SWEBench Pro v2 (Hard): 86.3 percent, against 88.2 percent for Kimi K3.
  • GPU kernel optimisation (PMPP-Hard): a mean of 54.25 of 69 tasks solved in 10 hours, against 55.25 for DeepSeek V4.1 Flash, 60 for Claude Opus 5.5 and 63 for GPT-6 Astra.

The training recipe is the more interesting part

The company says the model was trained with RL "on hundreds of thousands of long-horizon coding tasks across multiple agent harnesses and context-compaction strategies", and that it moved beyond unit-test rewards, with many tasks adding an agentic grader that judged how the model approached a problem. An early checkpoint was also tested on OpenCode under the name Fledge-Alpha. Training across several harnesses is a direct answer to a known weakness, where a model tuned to one loop falls apart in another.

That matters more given recent evidence about benchmark gaming. MaxxBench, published October 20, changed requirements in 89 DeepSWE tasks and found models talking themselves out of following a new instruction because they guessed what the hidden tests wanted. In one run a model implemented lowercase filenames correctly, saw an outside patch that omitted them, and removed its own correct code.

What remains uncertain. Every number above is from the vendor or from partners it selected, and the weights are not yet out, so nobody can reproduce them independently. The release date depends on safety testing that is still running. Thinking Machines says the model is a large step up in offensive cyber ability from Inkling Small while remaining behind the open-weight frontier, and that it "still trails closed-weights models" on its alignment evaluations.

Analysis: Wait for the weights before planning around this model, then test it on your own tasks with your own harness. At Belgavi's Book Store, Tanishka could run the same 50 refund and returns tickets through two open candidates with the requirements slightly reworded each time, and keep the model whose score holds up when the wording changes.

Sources and evidence

Inkling 2 Small is a 594B-parameter, 17B-active MoE model available through Tinker with closed weights; Apache 2.0 weights are promised next week after external safety testing. On the vendor's own table it trails DeepSeek or Kimi models on FrontierCode, DeepSWE and SWEBench Pro Hard. Treat all scores as vendor-reported until the weights can be tested.

Views are my own and do not represent any employer, past or present.