We are releasing AutoResearchExam, a benchmark on open-ended machine learning and engineering tasks. Our benchmark covers seven research areas including model training, data curation, AI safety and interpretability. benchmarks.bespokelabs.ai/au… In each task, we give agents 24 hours with a CPU or GPU machine to develop and improve their solutions through experiments and feedback. We measure both speed and quality with a combined score. Our benchmark has a unique feature: testing if agents create improvements that hold up on data they never see. We find that AI research agents often overfit as they try to improve. We see an interesting head-to-head comparison at the frontier: Astra starts the strongest and holds the lead for up to 19 hours but Fable 5.1 catches up and gets the top performing spot in the final hours. Qwen3.8 Max, Gemini 3.8 Flash and Grok 4.6 all sit on the cost-performance Pareto frontier, giving strong options at lower API budgets. Anthropic's Opus and Fable retain nearly all their validation performance on hidden tests, with gaps of 1.1% and 2.9%. Astra's improvement over Sol extends to generalization too, with that gap falling from 6.9% to 1.7%. (1/n)
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Congratulations Qiuyang and to the whole team for getting FrontierSmith accepted to NeurIPS!
Really happy to see FrontierSmith accepted to NeurIPS as a Spotlight! It’s been a great year working with @wenhaocha1 , and I’m very proud of what the FrontierCS team has built together. We also have more and more new work coming soon. Excited to share them!
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AutoResearchExam new leader today is Opus 5.5. It also resets the top end of the performance vs cost pareto, pushing Fable 5.1 and Astra 6 off the frontier!
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Alex Dimakis retweeted
benchmarks.bespokelabs.ai/au… Grok 4.7 added to our live leaderboard for AutoResearchExam. It jumps to position no3 at 30Min research, drops to 4, then again at no3 at 4h, landing at position no4 after 24h of AutoResearch. Pretty good performance and cost tradeoff overall!
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Alex Dimakis retweeted
We pretrained a 2.3B MoE (360M active) Hybrid Mamba-2 that lands within a few points of Llama-3.2-3B using <1% of its pretraining FLOPs. No dedicated cluster. The run hopped between H100s, A100s, V100s (yes, V100s) and TPU v5p/v6e on a single codebase. Meet Rigel 🧵
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Thanks Emad for highlighting AutoResearchExam and the role of different harnesses
Replying to @EMostaque
The @bespokelabsai blog post on Autoresearch exam is worth reading, shows minimal difference in performance with standard harnesses Much more to come, reliable frontier is within reach for all benchmarks.bespokelabs.ai/au…
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Alex Dimakis retweeted
Jev is not open-source and only available via API. Here's an open version called Nimble which performs just as well. github.com/bespokelabsai/nim…
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We lost our CEO for 2 days and then he came back with this awesome 9B model.
Introducing Bespoke Nimble: an open data, open model, open recipe for an open Jev. Code and info: github.com/bespokelabsai/nim… Model: huggingface.co/bespokelabs/B… Data: * A new data curation recipe called contrastive data curation. * Slightly change facts to generate negative data. This pushes the model to discriminate better and become a better decision maker. The calibration is implicit. * Didn't do ablations but I think this is a critical piece! * This also means training data doesn't need probabilities. * Data covered 10 categories, and is fully synthetic. * This data is split into train and eval. Training * LoRA finetune of Qwen3.5-9B. * Distillation-free: we use Jev to only evaluate. * No RL yet! Serving * Parallel constrained decoding as suggested by @NielsRogge and @harshagundal. Results: * The post-trained Qwen (Nimble) became substantially better on our curated eval: 66% for Qwen to 90% for Nimble. Jev is at 93%. * 100ms on H100 and free to use on your macbook! Feel the AGI for free. * 2 days of building in public. :) Big caveat is that there is no standard benchmark to measure performance, and it's possible Nimble is much worse on other benchmarks compared to Jev. But it should be better than Qwen! We thank @typesafeai for making Jev and the inspiring discussions in the community. Hope this release lifts all the boats and encourages more research and activity in this space.
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I think it is unfair to characterize Terminal Bench 4 simply as 'Flawed' or 'Broken' as done in this post: TB4 is a massive community effort. The bugs mentioned are known and public on Github, and the community is working on fixing them. E.g. saying: 'Terminal Bench 4.0 we found 45.5% of tasks to be broken after reviewing github issues.' is like saying open-source software is BROKEN because some people have found some bugs, raised issues, and the open-source community has not fixed them yet. Further, in TB4 the current task flaws affect less than 3 percent of rollouts on the leaderboards. It would be much more useful for a quality audit to find new issues that are not currently known.
Introducing Benchmark Reviews: our new initiative to audit AI benchmarks. We are launching with 15 benchmarks: 4 Verified, 9 Flawed, and 2 with not enough information for a review.
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This pleasant feeling of seeing evidence that doing highly unpleasant things only suggests benefits due to selection bias and poor controls.
We just published the largest review of cold exposure for mental health
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More data from our experiment on agents vs humans on 14 day tasks. We compare human expert coders to coding agents on the same tasks (from AtCoder Heuristic Contest). The exciting finding is that humans scale super-linearly. This is evidence that humans do continual learning, while they are solving a problem! I.e. they learn more about the coding problem they are trying to solve and scale fundamentally better compared to randomly trying things in a memoryless fashion. This result consistently happens for different harnesses and problems. We release our paper on this: arxiv.org/pdf/2609.15309 One interesting finding as an example: If you're planning to spend 5M tokens for a problem you should have one claude code session. If you have 30M you should have 2 sessions running independently for 15M each, and pick the best. If you have 100M token budget, you should have 3 sessions run independently and pick the best. Obviously communication between agents should do much better than this naive split of independent agents, but this has not been measured in a controlled way, as far as I know.
🧵 With unlimited compute, how fast can agents surpass humans? We introduce Elo-per-token analysis to profile agent performance curves across multiple open-ended tasks. • Agents initially scale faster than repeated sampling, but over long horizons converge toward their theoretical log-linear scaling curve. Humans, in contrast, improve superlinearly. • These curves also tell us how to spend test-time compute: the scaling inflection point gives a simple rule for splitting a fixed budget across agent sessions. Split a long run in a principled way, and you can get significant gains over a single run. • Fitting human-time and agent-token curves also gives us a fun way to translate AI compute into human time. Taking OpenAI’s ~130B-token Navier–Stokes run as input and extrapolating across the two curves gives an equivalent of ~41 years of work by a mathematician at 8 hours/day 😮.
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This unfortunate feeling of seeing evidence that doing highly unpleasant things can be good for you.
A 30-second cold blast at the end of your shower cuts sick days by 29 percent. A 2016 trial of 3,018 adults in the Netherlands is the largest cold-shower study ever done. Geert Buijze at the Academic Medical Centre in Amsterdam split participants into four groups: 30, 60, or 90 seconds of cold water at the end of a shower, or no cold water. They did this for 30 days straight. All three cold groups had 29 percent fewer sick days. The length did not matter. Thirty seconds worked as well as ninety. The mechanism is thought to involve the immune system. Brief cold exposure triggers a spike in white blood cell count and an increase in metabolic rate, both of which are part of the body's response to what it perceives as a physical threat. Over time, repeated cold exposure appears to train the immune system to respond faster and more efficiently to infections. The study also found that 91 percent of participants in the cold-water group said they would continue the practice after the trial ended, even though most of them described the experience as unpleasant. They reported feeling more energetic, and the energy boost was the reason they kept going. Thirty seconds. At the end of the shower you were already taking. The water does not have to be ice cold. It has to be cold enough to make you gasp, and you have to stay in it for a count of thirty. pubmed.ncbi.nlm.nih.gov/2763…
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AutoResearchExam harness and instructions for running your own harnesses released.
Releasing AutoResearchExam harness along with a setup and scoring guide for running the benchmark with your own custom harness. Eager to see your experimental insights! Harness: github.com/bespokelabsai/Aut… Custom harness guide: github.com/bespokelabsai/Aut…
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Introducing SkySynth: Enough with general-purpose systems that support many workloads and hardware configurations. SkySynth can write (on the fly!) an inference engine specific to the model/GPU and workloads you want to serve (eg Qwen3-4B 2.2x faster throughput compared to SGLang and vLLM) and a custom router that is 2x lower cost compared to generally optimized routers. Finally, a router that cares about your personal needs :p
Agents let us build systems for different workloads and requirements. But… can we trust what they build? We release 🌟SkySynth🌟: an engine for synthesizing high-performance, just-in-time (JIT) systems we can trust, by co-evolving formal proofs and tests alongside the code. Results: 💿 KV stores up to 2.3× faster than Redis and FASTER + formally verified stores with 2.9× Claude Code's pass rate 🚏 Model routers up to 48% cheaper than a general router ⚡ Specialized inference engine with 2.2× the throughput of vLLM/SGLang 🧵👇
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2026 survey of agents is here
The agent ecosystem is evolving rapidly and we are trying to capture a picture of where we are and where things are headed. We're now collecting responses for the 2026 survey of agents. berkeley.qualtrics.com/jfe/f… Help us create a more complete picture of how agent systems are evolving, what challenges remain, and where future research may be most impactful.
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We are releasing AutoResearchExam, a benchmark on open-ended machine learning and engineering tasks. Our benchmark covers seven research areas including model training, data curation, AI safety and interpretability. benchmarks.bespokelabs.ai/au… In each task, we give agents 24 hours with a CPU or GPU machine to develop and improve their solutions through experiments and feedback. We measure both speed and quality with a combined score. Our benchmark has a unique feature: testing if agents create improvements that hold up on data they never see. We find that AI research agents often overfit as they try to improve. We see an interesting head-to-head comparison at the frontier: Astra starts the strongest and holds the lead for up to 19 hours but Fable 5.1 catches up and gets the top performing spot in the final hours. Qwen3.8 Max, Gemini 3.8 Flash and Grok 4.6 all sit on the cost-performance Pareto frontier, giving strong options at lower API budgets. Anthropic's Opus and Fable retain nearly all their validation performance on hidden tests, with gaps of 1.1% and 2.9%. Astra's improvement over Sol extends to generalization too, with that gap falling from 6.9% to 1.7%. (1/n)
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(2/n) AutoResearchExam allows us to study what agents are doing during 24 hour research tasks. For example, we find that GPT-5.6 Sol tuned hyperparameters in over half the research rounds we observed. In contrast, Fable and Opus spent much less time doing hyperparameter tuning and tried to find new ideas or find a substantive fix We also saw Fable and Opus test several variants locally before submitting, so submission counts don't capture all their experiments. We share more of these behaviors in our blog, along with what happens when we give agents hints or change their harness. We will be growing and maintaining our benchmark and excited to work with AI researchers working towards RSI!
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(3/n) The central idea is to keep a hidden test set and see how the model performs as it does research. We define the Area Under the Auto Research Curve (AUARC): the hidden test reward curve. Its very interesting to see how models can overfit and others be more careful, and AUARC rewards good research behavior.
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