Cognition Releases SWE-2: A Kimi K3 Post-Trained Coding Model That Matches Fable 5.1 on FrontierCode at 64% Lower Cost

Overview

Cognition, the company behind the Devin coding agent, has released SWE-2, its most capable coding model to date. SWE-2 is post-trained with reinforcement learning from Kimi K3, Moonshot AI's 2.8T-parameter open model. Cognition reports a score of 50.0% on FrontierCode 1.1 Main, within 1 point of Fable 5.1 at 64% lower cost. It is also Cognition's first model with selectable reasoning-effort levels, all trained in a single RL run.

Deployment

SWE-2 is not deployable on your own infrastructure. It has no open weights and no standalone API. It runs only inside Devin: Desktop and CLI today, with Devin Web and Fusion rolling out.

What is SWE-2

SWE-2 builds on the infrastructure and recipe behind SWE-1.7, which was post-trained from Kimi K2.7. This time Cognition scaled RL to the multi-trillion-parameter regime, using a base model with almost 3x the parameters. Cognition says its RL still finds substantial headroom on top of K3, adding 5 to 6 points on many benchmarks.

The main change is an RL algorithm that trains all 3 effort levels in one run. Each level carries its own cost penalty, so the whole cost-and-performance frontier moves at once.

Benchmark Results

Cognition published the following table. Public results are used where available; otherwise each model runs in its native harness at best effort.

Benchmark SWE-2 Kimi K3 Grok 4.6 Fable 5.1 GPT-5.6 Sol GPT-6 Astra SWE-1.7
FrontierCode 1.1 Main 50.0% 44.2% 48.0% 50.9% 47.5% 53.3% 42.0%
DeepSWE 1.1 73.0% 68.5% 67.5% 67.4% โ€”

Editor's note: The original article includes a full benchmark table; the excerpt above shows the first two rows. All technical terms and results are preserved as published.

via MarkTechPost

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