
Building agents @TechAtBloomberg; Previously Postdoc @jhuclsp JHU; PhD @GeorgiaTech
Joined September 2015
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Fan Bai retweeted
Accepted to #NeurIPS2026 #NeurIPS π₯³ We've added more experiments and new findings; stay tuned for the camera-ready version.
Multimodal LLMs can read text in images, but why do they often perform worse than when the same text is given as tokens? Our work studies the modality gap of models perceiving text as pixels and shows how to close it.
π arxiv.org/abs/2603.09095
π§΅π #NLProc #LLM #ComputerVision
Fan Bai retweeted
When New Information Conflicts with What AI Knows
LLMs often continue to rely on information learned during training, even when instructed to use new information.
Coverage of our ACL 2026 paper
clsp.jhu.edu/2026/07/27/whenβ¦
aclanthology.org/2026.findinβ¦
@KaiserWhoLearns @loadingfan
Fan Bai retweeted
π₯FIRE-Bench got into #ICML2026π
Our take on #AutoResearch: target real human-verified scientific insights, not engineered ML models
Stay tuned for two follow-ups:
1οΈβ£ FIRE-Bench scaled into the "SWE-Bench" of research agents
2οΈβ£ Paper2Bench: any paper β a verifiable benchmark
π€π¬ Can AI actually do science end-to-end?
π§ π And how would we know when it matches, or surpasses, humans?
β‘π§ͺ AI is rapidly automating scientific discovery, but benchmarking full-cycle discovery, from π‘ ideation β π§βπ» execution β π conclusions, remains unsolved:
π§π§π§
βπ οΈ Open-ended discovery β manual validation (costly, unscalable)
βπ Metric-driven benchmarks (e.g., MLE-Bench) β convenient but narrow (is higher accuracy really enough?)
βπ€βοΈ LLM-as-judge β useful, but fundamentally risky if used alone
π₯π Introducing FIRE-Benchπ₯: Fullcycle Insight Rediscovery Evaluation
ππ firebench.github.io
πβ¨ A benchmark that turns fresh, human-verified insights from recent π NeurIPS / ICLR / ICML papers into masked, end-to-end discovery challenges π§©
ππ Constrained open-ended discoveryβbacked by ground truth.
π Key takeaways:
1β£ ππ§± Reference-based evaluation still matters: constrained LLM judging helps, but human-grounded references remain essential until agents can consistently match human conclusions
2β£ ππ§ Expert-validated ground truth: all tasks come from recent NeurIPS / ICLR / ICML papers, with contamination carefully controlled
3β£ ππ Rediscovery, not reproduction: original π§ͺ methods, π experiments, π» implementations, and π analyses are fully masked to create real discovery challenges
π Key empirical findings:
π‘ The "Science Gap" is Real: Even the best setup (Claude Code + Sonnet-4) caps out at an F1 score of 46.7. On hard tasks, agents struggle to break 30
π‘ Success is a "Lottery": Performance has incredibly high variance. Reliability is a major unsolved issue.
π‘ Coding is no longer the bottleneck; high-level reasoning and analysis are: ~74% of errors stem from flawed planning, not coding
βοΈ How it works:
πΉ Research-Problem Trees: We parse papers into trees (from broad roots to concrete leaves). This allows us to select intermediate nodes that perfectly balance open-ended exploration with verifiable ground truth.
πΉ Claim-Level Evaluation: We match AI conclusions against human conclusions using granular claim decomposition (F1 score).
πΉ Creativity Check: We score false positives to see if agents are finding novel truths (Spoilerπ¨: they arenβt creative yet).
πΉ New Diagnostic Taxonomy: failures traced across four stages: π§ Planning β π οΈ Implementation β βΆοΈ Execution β π§Ύ Conclusion
πΉ Additional Analyses: cost efficiency, contamination checks, and more.
π The Future:
π Live-FIRE-Bench: a live, continuously updated FIRE-Bench to track real-time progress on the latest research (Newest LLMs should be benchmarked with the newest research)
π Stronger scaffolding (search + planning + coding) π§ π§° and converting FIRE-Bench into interactive environments for training research agents
π Toward real creativity: We want better systems that can produce genuinely novel conclusions toward creativity π¨β³
π Better systems π§ β¨ and better benchmarks π must co-evolve π over time
ππ₯ Paper, video, demo, and research trees:
ππ firebench.github.io
#AI π€ #MachineLearning π #AI4Science π¬ #LLMs π§ #Research π§ͺ #AgenticAI π #FireBench π₯
Excited to share our latest work on the modality gap in multimodal LLMs.
Imagine an agent interacting with the real world as humans do. The text it encounters on signs, documents, or screens appears as pixels, not tokens. Yet MLLMs often perform worse when reading the same text from images. We study this gap and show how to close it.
Multimodal LLMs can read text in images, but why do they often perform worse than when the same text is given as tokens? Our work studies the modality gap of models perceiving text as pixels and shows how to close it.
π arxiv.org/abs/2603.09095
π§΅π #NLProc #LLM #ComputerVision
Fan Bai retweeted
Love this direction from @karpathy. Autonomous agents iterating on training runs feel like a modern renaissance of AutoML, except now the search space includes research decisions themselves: architectures, training setups, analysis pipelines, etc.
But if βautoresearchβ becomes a thing, the obvious question is: how do we measure progress in βautoresearchβ?
- Paper generation, single metrics, LLM-as-judge, or traditional reproducibility research?
Thatβs exactly the motivation behind FIRE-Bench (Full-cycle Insight Rediscovery Evaluation): xitter.cf/zhenwang9102/status/20β¦
Instead of optimizing a single metric or judging papers, FIRE-Bench evaluates whether agents can rediscover real scientific insights from recent NeurIPS / ICLR / ICML papers:
- Turn papers into research-problem trees and select a proper research problem to ask (neither too broad nor too narrow)
- We mask the original methods, experiments, and conclusions
- Ask agents to go from idea β implementation β experiments β conclusions
- Then score them via claim-level matching against expert-validated ground truth
What we found so far:
- Even the strongest agents struggle (best F1 β 46.7)
- Performance is extremely high variance (βresearch lotteryβ)
- Planning and reasoning, not coding, is the main bottleneck
If autoresearch systems like this keep improving, benchmarks must evolve alongside them.
Better research agents π€ need better ways to measure real discovery π¬
FIRE-Bench: firebench.github.io
I packaged up the "autoresearch" project into a new self-contained minimal repo if people would like to play over the weekend. It's basically nanochat LLM training core stripped down to a single-GPU, one file version of ~630 lines of code, then:
- the human iterates on the prompt (.md)
- the AI agent iterates on the training code (.py)
The goal is to engineer your agents to make the fastest research progress indefinitely and without any of your own involvement. In the image, every dot is a complete LLM training run that lasts exactly 5 minutes. The agent works in an autonomous loop on a git feature branch and accumulates git commits to the training script as it finds better settings (of lower validation loss by the end) of the neural network architecture, the optimizer, all the hyperparameters, etc. You can imagine comparing the research progress of different prompts, different agents, etc.
github.com/karpathy/autoreseβ¦
Part code, part sci-fi, and a pinch of psychosis :)
Really excited to co-lead this work. π
Agentic AI for scientific discovery is moving fast β but itβs not there yet.
Across FIRE-Benchπ₯, even SOTA agents (e.g., Claude Code and Codex) stay <50 F1, struggling with research planning and drawing valid conclusions from experiments. More strikingly, performance variance across runs is huge, highlighting how brittle current agents are on long-horizon, full-cycle research tasks.
Lots of room to push forward. π¬π€
π€π¬ Can AI actually do science end-to-end?
π§ π And how would we know when it matches, or surpasses, humans?
β‘π§ͺ AI is rapidly automating scientific discovery, but benchmarking full-cycle discovery, from π‘ ideation β π§βπ» execution β π conclusions, remains unsolved:
π§π§π§
βπ οΈ Open-ended discovery β manual validation (costly, unscalable)
βπ Metric-driven benchmarks (e.g., MLE-Bench) β convenient but narrow (is higher accuracy really enough?)
βπ€βοΈ LLM-as-judge β useful, but fundamentally risky if used alone
π₯π Introducing FIRE-Benchπ₯: Fullcycle Insight Rediscovery Evaluation
ππ firebench.github.io
πβ¨ A benchmark that turns fresh, human-verified insights from recent π NeurIPS / ICLR / ICML papers into masked, end-to-end discovery challenges π§©
ππ Constrained open-ended discoveryβbacked by ground truth.
π Key takeaways:
1β£ ππ§± Reference-based evaluation still matters: constrained LLM judging helps, but human-grounded references remain essential until agents can consistently match human conclusions
2β£ ππ§ Expert-validated ground truth: all tasks come from recent NeurIPS / ICLR / ICML papers, with contamination carefully controlled
3β£ ππ Rediscovery, not reproduction: original π§ͺ methods, π experiments, π» implementations, and π analyses are fully masked to create real discovery challenges
π Key empirical findings:
π‘ The "Science Gap" is Real: Even the best setup (Claude Code + Sonnet-4) caps out at an F1 score of 46.7. On hard tasks, agents struggle to break 30
π‘ Success is a "Lottery": Performance has incredibly high variance. Reliability is a major unsolved issue.
π‘ Coding is no longer the bottleneck; high-level reasoning and analysis are: ~74% of errors stem from flawed planning, not coding
βοΈ How it works:
πΉ Research-Problem Trees: We parse papers into trees (from broad roots to concrete leaves). This allows us to select intermediate nodes that perfectly balance open-ended exploration with verifiable ground truth.
πΉ Claim-Level Evaluation: We match AI conclusions against human conclusions using granular claim decomposition (F1 score).
πΉ Creativity Check: We score false positives to see if agents are finding novel truths (Spoilerπ¨: they arenβt creative yet).
πΉ New Diagnostic Taxonomy: failures traced across four stages: π§ Planning β π οΈ Implementation β βΆοΈ Execution β π§Ύ Conclusion
πΉ Additional Analyses: cost efficiency, contamination checks, and more.
π The Future:
π Live-FIRE-Bench: a live, continuously updated FIRE-Bench to track real-time progress on the latest research (Newest LLMs should be benchmarked with the newest research)
π Stronger scaffolding (search + planning + coding) π§ π§° and converting FIRE-Bench into interactive environments for training research agents
π Toward real creativity: We want better systems that can produce genuinely novel conclusions toward creativity π¨β³
π Better systems π§ β¨ and better benchmarks π must co-evolve π over time
ππ₯ Paper, video, demo, and research trees:
ππ firebench.github.io
#AI π€ #MachineLearning π #AI4Science π¬ #LLMs π§ #Research π§ͺ #AgenticAI π #FireBench π₯
π€ LLMs can ace Olympiad math, yet struggle with something as βsimpleβ as NER β even with in-context learning (ICL)?
π‘ Our #EMNLP2025 paper answers why:
βLLMs are Better Than You Think: Label-Guided In-Context Learning for Named Entity Recognition.β @mdredze @jhuclsp
π TL;DR: The issue isnβt the LLM β itβs how we pick demonstrations.
π arxiv.org/pdf/2505.23722v2
1/8
Even vs strong fine-tuned models like GoLLIE-34B, DEER (with GPT-4o) is competitive β all without training πͺ
Training-free, label-aware, and robust.
LLMs can do NER β they just need better demonstrations.
8/8
Please check out π¦ Paper + Code for more details!
π arxiv.org/pdf/2505.23722v2π·
π» github.com/bflashcp3f/deerπ·
Fan Bai retweeted
Can LLM-simulated users replace expensive human evaluation for multi-turn conversations? Short answer: yes, if you model the user right.
With our SimulatorArena, we find that detailed user profiles (knowledge + message style) improve alignment with real human evaluation by 26% at <3% the cost.
#EMNLP2025 [1/6] π§΅
Fan Bai retweeted
What happens when an LLM is asked to use information that contradicts its knowledge? We explore knowledge conflict in a new preprintπ
TLDR: Performance drops, and this could affect the overall performance of LLMs in model-based evaluation.ππ§΅β¬οΈ 1/8
#NLProc #LLM #AIResearch
Glad to see my first project at JHU has been accepted to #ml4h2024. Here are a few key takeaways:
1. Naive prompting often produces "easy-to-learn" examples, and methods that promote syntactic diversity in LLM output don't address this fundamental issue.
Today at #ML42024: Clinical QA can help doctors find critical information in patient records. But where do we get training data for these systems? Generating this data from an LLM is hard. π§΅ @loadingfan
3. Scaling synthetic data narrows the gap with human-generated data, though the label quality of "hard-to-learn" examples remains the central bottleneck, which may be addressed through selective annotation.
Please checkout our paper and code for more details!
Paper: arxiv.org/pdf/2412.04573
Code: github.com/bflashcp3f/syntheβ¦

















