Professor @northeastern | Chief Economist @micro1_ai | Social Scientist @BKCHarvard

Boston, Geneva, Dubai
Joined August 2012
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Mark Esposito, PhD retweeted
very excited for the launch of LegalReasonBench, from the braintrust of our legal data lab at micro1. we set out to fill an industry gap: a multi-step, long-horizon legal reasoning benchmark. every task is entirely attorney-authored with evolving matters & requests, as opposed to one-shot evaluation. this benchmark is the closest representation of how legal professionals collaborate with AI agents to complete work; iterating on documents, debating concepts, and researching caselaw. some very interesting failure modes were revealed and I am looking forward to seeing future models overcome them!!
AI models can be as convincing as a lawyer, but can they complete the complex multi-step reasoning a real legal matter requires? Today we're excited to introduce LegalReasonBench, a new benchmark to explore this question and test models on realistic, long-horizon legal matters authored by practicing attorneys. More info in thread 🧵
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Mark Esposito, PhD retweeted
nothing to add onto this… our approach to robotics data perfectly laid out here
Why is robotics still so far behind AI? And what will it actually take to get to general-purpose robots? Ali Ansari (@aliansarinik), founder of @micro1_ai, which just passed $1B ARR selling data to AI labs, goes deep on the problem and explains what it actually takes to collect and build datasets for robotics. Worth the 10 minutes: • Robotics lags language models because there is no internet-scale pre-training dataset for the physical world. Ali argues it is almost entirely a data problem. • The real world has a much larger, three-dimensional action space, so the data investment is orders of magnitude greater. • Self-driving works because driving is a relatively structured task, with physical lines and guidelines, and we’ve spent a decade collecting data for it. • The main approach today: egocentric data, where humans do diverse everyday tasks on camera, then annotate and structure it. • Overtime, Robots could potentially collect and generate their own product data, but models have no innate sense of consequence, so humans will always be in the loop and supply the reward signal. • Are edge cases really more valuable? To automate the economy, models need the full distribution of work, and almost all of it is ordinary tasks, not elite expertise.
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Mark Esposito, PhD retweeted
AI models can be as convincing as a lawyer, but can they complete the complex multi-step reasoning a real legal matter requires? Today we're excited to introduce LegalReasonBench, a new benchmark to explore this question and test models on realistic, long-horizon legal matters authored by practicing attorneys. More info in thread 🧵
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As agents evolve, evaluations need to keep up. Knowing whether an agent is improving requires consistent measurement and evidence that progress carries through to real-world performance. Our Economic Research Unit explores this in its first paper. Learn more:
Most companies can’t determine whether their AI agents are genuinely improving and our findings reveal why. The Economics Research Unit (ERU) at @micro1_ai , which I am privileged to lead, has released its inaugural paper, co-authored with @liuzhang11 : “Reliability of AI Agents: Rater Effects, Drift, and the Return to an Evaluation Program.” Key Insights from 2,611 Real Production Interviews By tracking a live AI interviewing agent in production, we uncovered two major dynamics: 1) Your evaluation metrics may reflect reviewer bias rather than AI performance. The identity of the reviewer was a stronger predictor of scores than the timing of the interview. In fact, a single overly strict evaluator masked a genuinely improving agent, making it appear stagnant. Once adjusted, reliability metrics increased by half a standard deviation. 2) AI evaluations go stale after roughly five weeks. Performance drifted even without code updates or new deployments. Without ongoing testing, after five weeks you lose the ability to detect a change as significant as your largest release. A one-time evaluation tells you about the agent you had, not the agent you are running. Agents drift, so evaluation cannot be a launch-day event. It has to run continuously for as long as the agent is live. That is the principle behind Cortex, micro1's reliability layer for agents in production, and this paper shows why it matters. Measuring AI agents is not a mere compliance checkbox; it serves as core economic infrastructure. This research marks just the beginning for the ERU, with further studies on the horizon. micro1.ai/research/are-ai-ag…
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Most companies can’t determine whether their AI agents are genuinely improving and our findings reveal why. The Economics Research Unit (ERU) at @micro1_ai , which I am privileged to lead, has released its inaugural paper, co-authored with @liuzhang11 : “Reliability of AI Agents: Rater Effects, Drift, and the Return to an Evaluation Program.” Key Insights from 2,611 Real Production Interviews By tracking a live AI interviewing agent in production, we uncovered two major dynamics: 1) Your evaluation metrics may reflect reviewer bias rather than AI performance. The identity of the reviewer was a stronger predictor of scores than the timing of the interview. In fact, a single overly strict evaluator masked a genuinely improving agent, making it appear stagnant. Once adjusted, reliability metrics increased by half a standard deviation. 2) AI evaluations go stale after roughly five weeks. Performance drifted even without code updates or new deployments. Without ongoing testing, after five weeks you lose the ability to detect a change as significant as your largest release. A one-time evaluation tells you about the agent you had, not the agent you are running. Agents drift, so evaluation cannot be a launch-day event. It has to run continuously for as long as the agent is live. That is the principle behind Cortex, micro1's reliability layer for agents in production, and this paper shows why it matters. Measuring AI agents is not a mere compliance checkbox; it serves as core economic infrastructure. This research marks just the beginning for the ERU, with further studies on the horizon. micro1.ai/research/are-ai-ag…
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Mark Esposito, PhD retweeted
We recently observed a frontier model repeatedly trying to hack its way towards the right answer, displaying misaligned behavior that optimizes for cheating. Gemini 3.8 Flash searched its sandbox for hidden grading files. micro1’s flow qc detected this reward hacking behavior before the task was published. GPT-6.1 Sol, GPT-6 Astra, Claude Opus 5.5 and Grok 4.7 never did this.
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On October 30th, we’re kicking off the micro1 Eval Hackathon with a $10,000 prize pool! The challenge: Pick a task in your field that requires expert judgment, challenge a frontier AI model with tough, realistic scenarios to uncover its mistakes, then build a repeatable test in code with clear criteria for scoring the model’s answers. Bring the edge cases and judgment calls you encounter across software, finance, healthcare, law, science, engineering, or any field you know deeply. The hackathon is fully virtual and free to enter worldwide, with a $10k prize pool. 🥇 First place: $5,000 🥈 Second place: $3,000 🥉 Third place: $2,000 Compete solo, with coding skills or proficiency in AI coding tools. Open to experts with at least two years of professional experience. Free registration is now open. Join us via the link in replies.
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The most inspiring part of all of this, is to know that this is how the story starts, not ends. onwards always
about 3 years ago, micro1 lost 60% of its revenue overnight and almost went bankrupt. today, i'm proud to share we've surpassed $1B annual run rate while remaining historically profitable. it’s been a special journey. we’re grateful for every struggle, moment, and person who has been part of it. we've taken a very untraditional path to get here. our core team is only ~180 people, spanning 14+ countries, and fully remote. many of our decisions sacrifice hundreds of millions of revenue and slow us down short term. but we believe they compound into advantages that are impossible to replicate long term. the long term is now. these are the 8 principles that made micro1 a leader in the data industry and will soon make us number one: 1.) human 1st AI: treat the tens of thousands of experts helping train models with absolute best-in-class care. our goal is to make AI training one of the largest, highest paying, and most enjoyable job sectors in the world. 2.) U.S. first: we refuse to work with adversarial nations, or export data that improves models against the interests of Americans. 3.) long-term research over short-term ARR: invest in deep research, products, and infrastructure for years from now, not just the next customer pipeline. 4.) proper incentives for intensely hard work: no arbitrary requirements like 996. inspire people to work extremely hard with outlier incentive structures instead of forcing weekend work. we’ve maintained close to 100% core team retention as a result. 5.) stay lean and global: we’ve reached $1B run rate with ~180 people, and intend to slow team growth significantly from here. exceptional talent is found around the world, and pedigree is the wrong thing to over-index on. 6.) execution alignment: company to retain a streamlined board so we can optimize for the next several decades, remain light-weight and dynamic, and take bold & calculated risks. 7.) abundant intelligence improvement: invest in building data generation models to make high-quality datasets and RL environments dramatically less expensive and more abundant. 8.) scale data on realism and horizon: realism brings the complexity of the real world into training models, while horizon extends how long models can work and how much complexity they can handle. both have enormous room to scale, and we’re pushing the limits of both. additionally: after surpassing $500M run rate this summer, we priced our Series B at a $4B valuation, alongside a ~$25M tender to give our early employees liquidity as we build for the long term. the round was led by Dream Ventures, a longtime supporter and one of our earliest investors, alongside Microsoft, Javelin, Flybridge, G Squared, Up Partners, and LG. we’re also grateful to be backed by incredible industry leaders, including Guodong Zhang (co-founder of xAI), Andy Fang (CTO of DoorDash), Igor Babuschkin (co-founder of xAI), Behnam Neyshabur (founder of Mirendil), Jerry Tworek (ex-VP of Research at OpenAI), and many more. data is on its way to becoming the largest industry humanity has ever seen, and we're certain this is just the beginning. best, Ali
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Mark Esposito, PhD retweeted
we’re expanding m1 research & eng team. our mission is to increase the predictability & abundance of intelligence improvement we work on: -data stack end to end -scaling on realism -building data generation models -improving & increasing usage of AI based QC -building very scalable rollouts infra -building data engine to rapidly & accurately find failure modes -discovery engine for model success cases if interested, email [email protected]
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Mark Esposito, PhD retweeted
We agree with Congress, this data must be secured using the best technology on the market. Using a 3rd party tool doesn’t eliminate privacy risks - it simply shifts responsibility. The company purchasing data for model training should be held accountable for ensuring sensitive information is removed. At micro1 we will use our in-house PII transformation model, which outperforms every frontier model on all public 3rd party benchmarks.
More than 120 US lawmakers raised concerns about Alphabet's Google acquiring defunct carrier Spirit Airlines' internal data for $10 million to train AI systems, including employee records such as 100 million emails and 500 million Microsoft Teams messages reut.rs/4zms8kX
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You make this announcement with nonchalance but the magnitude of what you are achieving is beyond your own sense of perception Ali. This is huge. Imagine writing a post where there is a B after the number 1. Kudos brother. Really.
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Truly loved your narrative on your journey and on @micro1_ai ! What I love the most ( as an economist ) is your idea that solo founders take outlier decisions which are nonlinearly leading to outlier performance. The fuzzy logic of courage and vision are what we would call these days at m1, human brilliance..
thanks for having me Julian & for this U.S. first AI question. 🇺🇲
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Mark Esposito, PhD retweeted
"There are about 150 companies signing up every single day." Ali shut down a $7M run-rate startup to build what's now a $4B company. Solo Founders Podcast ep 31 is live with @aliansarinik of @micro1_ai. 04:10 The first thing he ever sold online 17:30 Three signals it's time to move on 24:40 The all-in Loom that deleted the revenue 31:45 "Only the founding team can inject risk" 35:50 He never knew co-founders existed 43:40 Threads, final actions, zero meetings 53:30 Inside the AI data wars 1:01:50 Why micro1 won't sell to America's adversaries 1:07:30 The case for and against going solo
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Have you ever asked yourself how agents interact in our life? Well we not only asked the question, we went beyond and measured them! Check this out!
Which personal agent is the best life assistant? Today we're releasing the micro1 PersonalAgentBench to help answer that, and we're paying real personal agent users to contribute to the benchmark. Personal agents can now book your flights, answer emails, and move your meetings around. That’s great, until one messages the wrong person or makes a purchase without confirming. Capability is not the same as trust. So we put four personal agents to the test: Instinct, Muse, Grok Bot, and Gemini Spark. We found that even when agents found the right information, they still often miss what matters, overshare, or make things up. To find out for yourself how your agent compares, you can join our benchmark. We’re paying the first 100 users to run our prompts and share their results.
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Mark Esposito, PhD retweeted
Preliminary benchmark results below with Gemini Spark taking the lead. View more here: micro1.ai/personal-agent-ben…
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Mark Esposito, PhD retweeted
Which personal agent is the best life assistant? Today we're releasing the micro1 PersonalAgentBench to help answer that, and we're paying real personal agent users to contribute to the benchmark. Personal agents can now book your flights, answer emails, and move your meetings around. That’s great, until one messages the wrong person or makes a purchase without confirming. Capability is not the same as trust. So we put four personal agents to the test: Instinct, Muse, Grok Bot, and Gemini Spark. We found that even when agents found the right information, they still often miss what matters, overshare, or make things up. To find out for yourself how your agent compares, you can join our benchmark. We’re paying the first 100 users to run our prompts and share their results.
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Mark Esposito, PhD retweeted
Introducing CortexRetrievalBench, a benchmark for evaluating retrieval and reranking systems on financial documents. As enterprises put AI models to work across real workflows, one of the biggest deployment challenges is getting the right information in front of the model, in the right order. CortexRetrievalBench pairs a corpus of financial documents with 140 diligence queries, each tied to the authoritative sources that should answer it. Systems are scored on whether they retrieve those documents and whether they rank them at the top. The challenge becomes most apparent when multiple documents appear suitable to answer the same question. In financial research, several documents can look relevant to the same question, such as a current filing and a superseded one, or a primary source and a secondary summary. Across the systems we tested, an authoritative document appeared in the top 10 results for 92–99% of queries, but ranked first for only 42–69%. The result points to a specific weakness. Retrieval systems often find the right evidence, but fail to put it ahead of weaker alternatives. When research informs real-world decisions, the source ranked first can end up shaping the evidence the model relies on. Full report linked in the replies.
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