MLAgentBench
Agents run machine learning experiments on 13 tasks, from improving CIFAR-10 accuracy to research problems like BabyLM. They read and write files, run code and inspect outputs.
An early AI R&D agent benchmark from 2023. About 360 GitHub stars and 75 forks.
- Made by
- Stanford University (SNAP)
- Released
- October 2023
- Kind
- Machine learning engineering
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- All public
- Last model added
- December 2023
- Scores refreshed
- November 12th, 2026
In the authors’ words
A central aspect of machine learning research is experimentation, the process of designing and running experiments, analyzing the results, and iterating towards some positive outcome (e.g., improving accuracy). Could agents driven by powerful language models perform machine learning experimentation effectively? To answer this question, we introduce MLAgentBench, a suite of 13 tasks ranging from improving model performance on CIFAR-10 to recent research problems like BabyLM. For each task, an agent can perform actions like reading/writing files, executing code, and inspecting outputs. We then construct an agent that can perform ML experimentation based on ReAct framework. We benchmark agents based on Claude v1.0, Claude v2.1, Claude v3 Opus, GPT-4, GPT-4-turbo, Gemini-Pro, and Mixtral and find that a Claude v3 Opus agent is the best in terms of success rate. It can build compelling ML models over many tasks in MLAgentBench with 37.5% average success rate. Our agents also display highly interpretable plans and actions. However, the success rates vary considerably; they span from 100% on well-established older datasets to as low as 0% on recent Kaggle challenges created potentially after the underlying LM was trained. Finally, we identify several key challenges for LM-based agents such as long-term planning and reducing hallucination. Our code is released at https://github.com/snap-stanford/MLAgentBench.
Claude v3 Opus tops the leaderboard with 37.5%
Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders. The best model we track is Gemini 1.0 Pro, at 18.3%.
- 1 Claude v3 Opus 37.5%
- 2 Claude v2.1 26%
- 3 GPT-4-turbo (snapshot unspecified) 26%
- 4 GPT-4 (snapshot unspecified) 19.2%
- 5
Gemini 1.0 Pro 18.3%
- 6 Claude v1.0 16.3%
- 7 Mixtral (size unspecified) 3.80%
Source: Official MLAgentBench leaderboard
| # | Entry | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude v3 Opus | 37.5% | Official leaderboard | ||
| 2 | Claude v2.1 | 26% | Official leaderboard | ||
| 3 | GPT-4-turbo (snapshot unspecified) | 26% | Official leaderboard | ||
| 4 | GPT-4 (snapshot unspecified) | 19.2% | Official leaderboard | ||
| 5 | | 18.3% | Dec 2023 | Official leaderboard | |
| 6 | Claude v1.0 | 16.3% | Official leaderboard | ||
| 7 | Mixtral (size unspecified) | 3.80% | Official leaderboard |
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Source: Official MLAgentBench leaderboard
No lab model card reports it yet
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark.
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