Quadruped reinforcement learning task (Anthropic)
Claude Opus 5 31.3 leads since July 2026
Only in system cards Agents train a quadruped to reach high performance in a continuous control task.
In-house Anthropic evaluation. The tasks are not public.
- Made by
- Anthropic
- Released
- May 2025
- Kind
- Machine learning engineering
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- Kept private
- Strongest model tested
- Claude Opus 5 #10 on the capability index
- Last in a system card
- July 2026
- Last model added
- July 2026
8
Models scored in lab cards
12
System cards report it, from 1 lab
Claude Opus 5 leads with 31.3 among models released by July 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 July 2026, and nobody has reported a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:
- Claude Fable 5.2
-
Gemini 4 Carbon - GPT-6 Astra
- Claude Opus 5.5
- and 15 more
- 1 Claude Opus 5 31.3
- 2 Claude Mythos Preview 30.9
- 3 Claude Opus 4.7 26.5
- 4 Claude Sonnet 5 19.9
- 5 Claude Sonnet 4.5 1.30
- 6 Claude Opus 4 1.25
- 7 Claude Opus 4.1 1.18
- 8 Claude Sonnet 4 0.35
Source: Labs’ model cards
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 5 | 31.3 | Jul 2026 | Lab model card | |
| 2 | Claude Mythos Preview | 30.9 | Apr 2026 | Lab model card | |
| 3 | Claude Opus 4.7 | 26.5 | Apr 2026 | Lab model card | |
| 4 | Claude Sonnet 5 | 19.9 | Jun 2026 | Lab model card | |
| 5 | Claude Sonnet 4.5 | 1.30 | Sep 2025 | Lab model card | |
| 6 | Claude Opus 4 | 1.25 | May 2025 | Lab model card | |
| 7 | Claude Opus 4.1 | 1.18 | Aug 2025 | Lab model card | |
| 8 | Claude Sonnet 4 | 0.35 | May 2025 | Lab model card |
4 models have held number one in labs’ own numbers since its release in May 2025
Lab claims count from the day the card came out, independent runs from the model’s release.
Anthropic
Source: Labs’ model cards
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Reported by the lab in its model card
Source: Labs’ model cards
Labs report it only in system cards
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark. Some system cards do, below.
12 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 |
|---|---|---|---|---|
| Jul 24, 2026 | Claude Opus 5 system card | 31.3 | Quadruped RL, highest score, no hyperparameters variant (Table 2.3.5.A) | AI R&D risk |
| Jun 30, 2026 | Claude Sonnet 5 system card | 19.9 | Quadruped RL, highest score with no hyperparameters 19.94 (Table 2.3.3.A) | AI R&D risk |
| Apr 16, 2026 | Claude Opus 4.7 system card | 26.5 | Quadruped RL, highest score, no hparams variant (Table 2.3.4.A) | AI R&D risk |
| Apr 7, 2026 | Claude Mythos Preview system card | 30.9 | Quadruped RL, highest score, no hyperparameters variant, 30.87 (Table 2.3.3.A) | AI R&D risk |
| Feb 17, 2026 | Claude Sonnet 4.6 system card | Quadruped reinforcement learning, highest score 18.72 no hyperparameter variant and 17.88 no reward function variant, no overall (6.3.3.5) | AI R&D risk | |
| Feb 5, 2026 | Claude Opus 4.6 system card | Quadruped reinforcement learning, two variants with no overall: highest score 20.96 no hyperparameter variant and 21.99 no reward function variant, threshold 12 (8.3.3.5) | AI R&D risk | |
| Nov 24, 2025 | Claude Opus 4.5 system card | Quadruped reinforcement learning, easy variants with no overall: highest score 19.48 no hyperparameter variant and 19.16 no reward function variant, threshold 12 (7.3.2.5) | AI R&D risk | |
| Sep 29, 2025 | Claude Sonnet 4.5 system card | 1.3 | Quadruped reinforcement learning, easier variant, best run normalized score 1.302 (threshold 1), median below threshold (9.3.3.5) | AI R&D risk |
| Aug 5, 2025 | Claude Opus 4.1 system card addendum | 1.18 | Quadruped locomotion, easier variant, 1 in 30 trials above threshold, scoring 1.183 (6.4.1) | AI R&D risk |
| May 22, 2025 | Claude Sonnet 4 system card | 0.35 | Quadruped reinforcement learning, easy variants, highest score 0.35 (threshold 1). An earlier snapshot scored at threshold (7.3.3.5) | AI R&D risk |
| May 22, 2025 | Claude Opus 4 system card | 1.25 | Quadruped reinforcement learning, easy variant without hyperparameters, best run normalized score 1.25 (threshold 1) (7.3.3.5) | AI R&D risk |
| Feb 24, 2025 | Claude 3.7 Sonnet system card | Internal AI Research Evaluation Suite, continuous control task variants 1 and 2, score distribution chart without printed values. Text says very far from the human baseline of 1.0 (Figure 21) | AI R&D risk |
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