Text-based reinforcement learning task (Anthropic)
Agents build scaffolding that improves a weaker model on a text-based reinforcement learning task.
In-house Anthropic evaluation. The tasks are not public.
- Level
- Expert Specialists with years of training, often over hours of work
- Scored
- Checked automatically A program checks the result against an answer key, unit tests or the expected final state.
- Answers
- Agent task Many steps in a terminal, browser, desktop, app, game or robot.
2 models share the top score of 0.97 among models released by Feb 2026
Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.
The newest model with a score here came out in Feb 2026, and nobody has reported a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- GPT-6 Astra
- Claude Opus 5.5
- GPT-6.1 Terra
- GPT-6.1 Sol
- and 16 more
- 1 Claude Opus 4.5 0.97
- 2 Claude Opus 4.6 0.97
- 3 Claude Sonnet 4.6 0.93
- 4 Claude Sonnet 4.5 0.85
- 5 Claude Sonnet 4 0.68
- 6 Claude Opus 4 0.63
- 7 Claude Opus 4.1 0.42
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 4.5 | 0.97 | Nov 2025 | Model card | |
| 2 | Claude Opus 4.6 | 0.97 | Feb 2026 | Model card | |
| 3 | Claude Sonnet 4.6 | 0.93 | Feb 2026 | Model card | |
| 4 | Claude Sonnet 4.5 | 0.85 | Sep 2025 | Model card | |
| 5 | Claude Sonnet 4 | 0.68 | May 2025 | Model card | |
| 6 | Claude Opus 4 | 0.63 | May 2025 | Model card | |
| 7 | Claude Opus 4.1 | 0.42 | Aug 2025 | Model card |
3 models have held number one since its release in May 2025
Lab claims count from the day the card came out, independent runs from the model’s release.
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Labs report it only in system cards
We read the headline results of 479 launch posts from 51 labs, and none of them list this benchmark. Some system cards do, below.
7 system cards report it, from 1 lab
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| 17 Feb 2026 | Claude Sonnet 4.6 system card | 0.925 | Text-based reinforcement learning task, best score 0.925 (6.3.3.3) | AI R&D risk |
| 5 Feb 2026 | Claude Opus 4.6 system card | 0.975 | Text-based reinforcement learning task, best score 0.975, threshold 0.9 (8.3.3.3) | AI R&D risk |
| 24 Nov 2025 | Claude Opus 4.5 system card | 0.975 | Text-based reinforcement learning task, best score 0.975, mean below the 0.9 threshold (7.3.2.3) | AI R&D risk |
| 29 Sep 2025 | Claude Sonnet 4.5 system card | 0.85 | Text-based reinforcement learning task, best score 0.850, threshold 0.9 (9.3.3.3) | AI R&D risk |
| 5 Aug 2025 | Claude Opus 4.1 system card addendum | 0.425 | Text-based RL, best score 0.425 (6.4.1) | AI R&D risk |
| 22 May 2025 | Claude Sonnet 4 system card | 0.675 | Text-based reinforcement learning task, best score 0.675 (7.3.3.3) | AI R&D risk |
| 22 May 2025 | Claude Opus 4 system card | 0.625 | Text-based reinforcement learning task, best score 0.625 (7.3.3.3) | AI R&D risk |
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