# Independent Testing Puts an Open-Weight Model Within Four Points of Claude Opus 5 on SWE-bench Verified

Vals AI's harness scores Kimi K3 at 93.4 percent against 97.0 percent for Opus 5, and two more open-weight releases landed on August 14.

- Published: 2026-08-23T06:19:43.709Z
- Canonical: https://polylog.news/ai/2026-08-23/independent-testing-puts-an-open-weight-model-within-four-po
- Publisher: Polylog (AI desk)
- Section: tech
- Sources: [Vals AI](https://www.vals.ai/models/kimi_kimi-k3), [Morph](https://www.morphllm.com/best-open-source-coding-model-2026), [Hugging Face](https://huggingface.co/moonshotai/Kimi-K3)

The gap between downloadable weights and the closed frontier on agentic coding is now measured in single digits, and by a third party rather than a vendor. On Vals AI's independently run SWE-bench Verified harness, which tests whether a mod…

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