AI Agents That Matter
Paper · 2024 · Sayash Kapoor, Benedikt Stroebl, Zachary S. Siegel et al.
Summary
Benchmarks steer the development of LLM-based agents. The Princeton authors argue that current evaluation habits reward topping leaderboards rather than building systems that work in practice. They identify four problems:
- Evaluations look only at accuracy and ignore inference cost.
- The needs of model developers and downstream builders are mixed up.
- Many benchmarks lack suitable held-out data, which invites overfitting and shortcuts.
- Procedures are not standardized, which undermines reproducibility.
To support these claims, they re-run published coding agents on HumanEval next to inexpensive baselines and plot everything on an accuracy–cost Pareto frontier. They also adapt DSPy to optimize cost and accuracy jointly on HotPotQA, and present case studies on NovelQA and WebArena. The cheap baselines match or beat elaborate agent designs for far less money. This leaves open whether reflection, planning or debugging actually cause the reported gains. The work matters because it gives practical guidance for telling real progress from hype: cost-aware comparison, holdouts matched to the intended generality, and shared evaluation tooling.
Key points
- Three baselines were tested on all 164 HumanEval tasks: retry (up to five calls at temperature 0), warming (temperature raised from 0 to 0.5) and escalation (Llama-3 8B → GPT-3.5 → Llama-3 70B → GPT-4). Warming shows no significant accuracy gap to the best complex agent among LDB, LATS and Reflexion.
- At similar accuracy, costs differ by nearly 100×. LATS costs over 50 times as much as warming, and Reflexion and LDB cost more than 1.5 times as much. Escalation is more accurate than LDB (GPT-3.5) at under half its cost.
- The authors define four levels of agent generality and argue that each requires a different type of hold-out set. WebArena illustrates how shortcuts arise when holdouts are missing.
- Reproducibility problems inflate reported accuracy:
- LATS and STeP counted some failed tasks as successes and dropped 1 and 8 tasks, respectively.
- Rate limits on WebArena's Reddit clone make task order matter.
- Evaluation is expensive: one full SWE-Agent run on SWE-bench (more than 2,000 tasks, capped at USD 4 each) could exceed USD 8,000. As a result, error bars are rarely reported.
Institutions
Fields, topics and concepts
📚 Shelves 2The field of science this work belongs to (OpenAlex fields).Computer Science · 18,614 worksArtificial Intelligence · 17,965 works
Cite
Cite as Sayash Kapoor, Benedikt Stroebl, Zachary S. Siegel, Nitya Nadgir and Arvind Narayanan. 2024. AI Agents That Matter. arXiv:2407.01502.
@misc{kapoor2024ai,
title = {{AI Agents That Matter}},
author = {Sayash Kapoor, Benedikt Stroebl, Zachary S. Siegel, Nitya Nadgir and Arvind Narayanan},
year = {2024},
doi = {10.48550/arxiv.2407.01502},
eprint = {2407.01502},
archivePrefix = {arXiv},
url = {https://doi.org/10.48550/arxiv.2407.01502}
}References
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