Internal model use survey (Anthropic)
Anthropic technical staff estimate productivity uplift from the model and judge whether it could automate a junior ML researcher.
Survey of Anthropic staff, not a task set.
- Level
- Expert Specialists with years of training, often over hours of work
- Scored
- Graded by people Human experts grade or compare the outputs.
- Answers
- Open-ended Free-form text, documents, designs or media judged as a whole.
Claude Opus 4.5 leads with 50% among models released by Apr 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 Apr 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 50%
- 2 Claude Mythos Preview 5.60%
- 3 Claude Opus 4 0%
- 4 Claude Sonnet 4.5 0%
- 5 Claude Opus 4.6 0%
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Opus 4.5 | 50% | Nov 2025 | Model card | |
| 2 | Claude Mythos Preview | 5.60% | Apr 2026 | Model card | |
| 3 | Claude Opus 4 | 0% | May 2025 | Model card | |
| 4 | Claude Sonnet 4.5 | 0% | Sep 2025 | Model card | |
| 5 | Claude Opus 4.6 | 0% | Feb 2026 | Model card |
2 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.
5 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 |
|---|---|---|---|---|
| 7 Apr 2026 | Claude Mythos Preview system card | 5.6 | Internal survey (n=18), 1/18 thought the model already was a drop-in replacement for an entry-level Research Scientist or Engineer, 4/18 gave it 50% odds with 3 months of scaffolding (2.3.4). A separate staff survey gives a productivity uplift geometric mean of about 4x (2.3.6) | AI R&D risk |
| 5 Feb 2026 | Claude Opus 4.6 system card | 0 | Internal model use survey, 0/16 participants believed the model could be a drop-in replacement for an entry-level researcher after follow-up (initial answers 11 unlikely, 3 likely, 2 already possible); productivity uplift mean 152%, median 100% (8.3, 8.3.1) | AI R&D risk |
| 24 Nov 2025 | Claude Opus 4.5 system card | 50 | Internal model use survey, 9/18 participants reported at least 100% productivity improvement, median 100%, mean 220%, 0/18 believed AI R&D-4 was crossed (7.3.4) | AI R&D risk |
| 29 Sep 2025 | Claude Sonnet 4.5 system card | 0 | Internal model evaluation and use survey, 0/7 researchers believed the model could completely automate a junior ML researcher. Productivity estimates ~100%, 15%, 20%, 20%, 30%, 40% (9.3.5) | AI R&D risk |
| 22 May 2025 | Claude Opus 4 system card | 0 | Internal model use survey, 0/4 researchers believed Claude Opus 4 could completely automate a junior ML researcher (7.3.5) | AI R&D risk |
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