One signal

Update

What changed

OpenAI says GPT-6.1 Terra solved 50.3% of tasks on Terminal-Bench 4.0 at maximum reasoning effort, compared with 21.5% for GPT-5.6 Terra. The benchmark tests coding agents on command-line work, including fixing a webpage whose layout shifts as it loads.

The company also reports a lower error rate on its internal benchmark of prompts designed to induce mistakes: 16.7% at low reasoning effort, down from 53.6% for GPT-5.6 Terra. At maximum effort, it says Terra’s rate was 4.3%. These are OpenAI’s own benchmark results, not independent tests.

OpenAI says GPT-6.1 Sol and GPT-6 Astra remain better choices for its most complex coding tasks. That is a useful boundary on the coding claim: Terra’s reported gains do not make it the top choice for every job.

Sources and evidence

• GPT-6.1 Terra: OpenAI says GPT-6.1 Terra scored 50.3% on Terminal-Bench 4.0 at maximum reasoning effort and lowered its internal low-effort error rate to 16.7%, compared with 53.6% for GPT-5.6 Terra.

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