Leanstral 1.5

(docs.mistral.ai)

303 points | by vetronauta a day ago ago

98 comments

  • Grimblewald a day ago ago

    Got curious, sign up, add money to account, try to use. Can't, it's a labs model. Fine, let's enable labs. Can't, unspecified error. Fine, lets contact customer support as instructed, can't no customer support, just a half-assed FAQ, that seems vibe-coded and searched poorly, totally irrelevant answers coming up for all queries tried. Then it hit me:

    If AI makes good customer support, then why does no AI company use theirs to provide customer support?

    • thih9 a day ago ago

      > If AI makes good customer support, then why does no AI company use theirs to provide customer support?

      They do! E.g. Cursor. See earlier discussions like "Cursor IDE support hallucinates lockout policy, causes user cancellations"[1].

      [1]: https://news.ycombinator.com/item?id=43683012

      • ray_v 16 hours ago ago

        thanks! I hate it!

    • saghm a day ago ago

      No one ever thought it made good customer support. It makes cheap customer support, and quite a lot of companies already have shitty customer support because they don't care about it being good, so they're thrilled to get to cut costs further.

      It's "good" from the perspective of a company that's annoyed to have to spend money on actually fixing things.

    • puppymaster a day ago ago

      I laughed and cried at this comment. It's so uncannily EU. Just spent 18 months landing an EU enterprise contract. Signed today and sent it back and got an automated message 'sorry will be on vacation til end of July...' This is the fourth vacation emails I got since corresponding with this contact window for the past 1 year.

      • throw1234567891 a day ago ago

        Yes, we have more vacation in the EU than people in the US.

        • falcor84 18 hours ago ago

          It's absolutely possible for individual employees to have generous vacations, while at the same time maintaining a continuously staffed support function.

        • JumpCrisscross 18 hours ago ago

          Eh, Europe has some great service cultures. (There was a recent comment citing an article contrasting its furniture and tech industries I’m having trouble finding.)

          European tech’s service culture is just distinctly and notoriously terrible, even within Europe.

        • ekianjo 16 hours ago ago

          it's more like nothing even happens in summer.

      • embedding-shape a day ago ago

        How is people having reasonable work place environments related to shit customer support and companies trying to optimize for reducing costs? Seems highly unrelated.

      • make3 10 hours ago ago

        launches suck in the US too. See: every single AAA game launch ever

    • begleri a day ago ago

      That's frustrating and odd because I can use the model for free (have never connected any form of payment)

      • henryrobbins00 20 hours ago ago

        Really? I get a 403 that I must enable Lab models on https://admin.mistral.ai/plateforme/privacy. When I try to do that, it gives "There was an error trying to update the Labs setting."

        Do you have that Labs setting enabled? When I contacted support, they said "enabling Labs models isn't available for self-serve activation on standard individual accounts." Do you have a different type of account?

    • criticalfault a day ago ago

      These guys don't answer emails. Same for qwant.

      Sample of two, but I'm assuming french companies don't like to being contacted n English.

      • MrToadMan a day ago ago

        If only they had access to a world class translation system, they could auto translate between languages effortlessly :)

        • GTP a day ago ago

          They're just offended by people not using their product :D

      • zelphirkalt a day ago ago

        Wasn't there a thread recently, about them disappointingly being also just a US company, just with an office in France?

    • Mashimo a day ago ago

      Further down someone said the support is great and they respond within the day.

      • Grimblewald 11 hours ago ago

        I did get a refund quite quickly, after I finally figured out how to contact their support, which in some stroke of cosmic humor took deepseek to figure out because using their website left my trapped in a dead-end loop. Asking mistral for help lead to links that all 404'd or the same useless help section / faq page.

    • sajithdilshan 16 hours ago ago

      You got the authentic European customer support. In America the customer is king and in Europe the customer is shit

      • victorbjorklund 16 hours ago ago

        Yea, because the tech gigants are known to have a good support. You won’t be talking to a real human in Google, Facebook, OpenAi if you are just a normal consumer/tiny business.

      • poszlem 16 hours ago ago

        Oh really? Then why did I have to submit a google form to anthropic asking them to unblock me for something they never even explained? They ignored my request, then a week later sent me a message saying I had been unblocked, yet I still couldn’t log in. And there was still no way to speak to anybody with a spine or a brain? Is that the treatment your american kings get?

    • bitlad 13 hours ago ago

      Atleast the UI looks nice. But I'm having trouble navigating it.

    • blueTiger33 a day ago ago

      they are working on LeChaton fat

    • tmikaeld a day ago ago

      This isn’t the first time. I’m amazed at how they manage to fumble releases over and over …

    • adithyassekhar a day ago ago

      Because that AI will either expose their business or it will be so nerfed it’s useless.

    • gregman1 a day ago ago

      “Don’t get high on your own supply” - I think it’s Microsoft’s motto.

    • SimonMistral 18 hours ago ago

      Fixed, sorry for that!

    • roysting a day ago ago

      Mostly political, economic, and social ramifications.

  • henryrobbins00 a day ago ago

    What a coincidence! I just released OpenATP earlier today. OpenATP is an open-source Python package and CLI for agentic automated theorem provers. It includes support for Leanstral with Mistral’s Vibe harness. The previous production Leanstral model was deprecated on May 22nd. I will update the package to point to Leanstral 1.5 ASAP!

    GitHub: https://github.com/henryrobbins/open-atp

    Docs: https://open-atp.henryrobbins.com

  • helloplanets a day ago ago

    Tangential, but I'm pretty sad about EU having absolutely nothing in the actual SotA LLM market. Especially given the recent events of US completely restricting the actual SotA models.

    Has this been just pure lack of funding and infra?

    • troyvit 18 hours ago ago

      Mistral is generally winning the fights it chooses to fight and that's what they need to do.

      Instead of looking at what EU's economy could contribute towards a SotA model it's more accurate to look at what France's economy could contribute, then compare that to the US or China. The scale isn't there. Instead what I like to see is what they can accomplish with that lower scale, and it's stuff like Leanstral, Voxtral and other niche products.

    • Epa095 a day ago ago

      Software in general, AI as well, is a rich get richer market. The big American companies can afford to (and very much do) scoop up European talents and upcoming European companies. And if they don't want to buy them, they can undercut them to bankruptcy. We live in a colony economy, with human capital as the raw produce, and it all gets funneled to the USA.

      The only way to avoid this is to stop playing the game as it is today, and start using proper industrial policy to build up a competitive industry (like China did). There has been no appetite for that the last decades, but Trump is making it completely clear that the state is back, and Europe is slowly acknowledging it as well.

      • hsuduebc2 18 hours ago ago

        Europeans should thank Trump for that. Digital sovereignty became a major theme mostly because his hollow head could not comprehend the previous strategy.

        I would say it is mostly a money problem rooted in the culture. VC funding is not nearly as common in Europe. Not that many people are willing to risk serious money the way US corporations do, or even ordinary Americans through the stock market. Banks will never lend you money for this.

        That itself makes it really easy to poach great engineers. You can earn very good money in Europe, but usually not the best money.

        If the EU wanted to pour billions into AI labs, national governments would immediately start fighting over which country should host them. These petty disputes, coming from hundreds of years of Europeans killing each other, are one of the main things holding them back.

        I believe that in the end, the strategy will be to watch what worked and what did not work for the Americans, then simply copy it. But Europe was never really cut off from crucial technology before, so I'm curious if that will have any interesting solution.

    • msdz 17 hours ago ago

      > Has this been just pure lack of funding and infra?

      For the most part, yes.

      France and Germany are the two biggest EU economies. France has well, Mistral, and we here have a government-funded VC entity that is way too proud [1] to be able to offer a whopping… €125 million (<$150 M USD) for helping European researchers achieve new SOTA in sovereign models. And that sum is not even going to a single challenge winner, it'll be split up among multiple recipients. Don't get me wrong, this is a cool first step, or rather, would have been one about three to four years ago.

      It's a pity, really.

      [1] (in German) https://www.sprind.org/worte/magazin/verkuendung-next-fronti...

    • mike_hearn a day ago ago

      Mistral has raised $4B+ which is a decent chunk of change, albeit not in the league of OpenAI/Anthropic/xAI.

      The hard part is justifying pure LLM development financially. Models are all very similar. OpenAI justified it originally by being a 'charity' dedicated to pure research (not financial). Anthropic justified it by saying OpenAI didn't care enough about safety and splitting from them (not financial). Elon justified it by saying that AI would be woke and untruthful unless he built Grok (not financial). Google did Gemini because, well, they're where it all started and because AI research was one of the core missions Larry & Sergey gave it when they started it (but then sat on it for financial reasons).

      Then there's the Chinese models. It's unclear what their motives are tbh. I've never seen a really great explanation, only hypotheses. But as they're giving them away for free or very underpriced, their motivation doesn't seem to be financial either.

      But Mistral is a normal company. It doesn't have rich backers giving it money based on narratives about cosmic destiny, so it needs to justify what it's doing with ROI. So that more or less rules out large scale LLM training.

      There's also EU regulation to consider. When I looked at this in the past I found lots of odd rules that kill off any chance of having a European tech industry. The UK had one that said you could only crawl the internet for research purposes!

      https://knowledgerights21.org/news-story/the-uks-copyright-l...

      And without the First Amendment you're at much greater risk of being prosecuted for things your models say. See how Germany has taken Google to court over things its models put in its search result pages.

      So the benefit isn't clear and the legal risks are very high.

      • ghm2199 a day ago ago

        Someone commented on this page that their main market are long term b2b contracts. If that’s true then what you are saying isn’t a problem.

        • mike_hearn an hour ago ago

          Right, they pivoted, but originally they were a pure play LLM developer.

    • Sol- a day ago ago

      The EU simply doesn't have a proper common market, especially when it comes to capital. Having more people than the US and a big economy in aggregate doesn't matter much if you can't efficiently pool resources. Could we in Europe have 100 billion fundraises for a new lab? If not, then it's over and you can give up.

      • Epa095 a day ago ago

        I agree with your analysis, at least as long as we shall remain strictly inside the free market methodologies. And having a common capital market would be good no matter what.

        But there are other ways to pool resources than the free market. Airbus was not made dynamically in a market, neither was the LHC. 100 billion € is a lot, it's half of the total allocated aid from Europe to Ukraina. Which can be read in two ways, either 'helping Ukraine is already weighing us down, another similar cost is too much for some IT toy ', or 'Europe has the ability to collect massive amount of capital when it needs to, and AI is a existential threat which justifies it'.

    • derfurth 20 hours ago ago

      One could make the case that being SotA in 2026 is very costly and not that important for being SotA in 2030 if much more efficient models indeed happens.

    • JumpCrisscross 18 hours ago ago

      How much does supporting multiple languages as first-class citizens (versus adding a translation layer) cost a model?

      • anthonypasq 18 hours ago ago

        absolutely nothing id imagine? you think all the chinese are using their models in english?

    • segmondy 17 hours ago ago

      Culture

  • c7b a day ago ago

    I'm not sure I understand the Weights policy. This site says the weights are Apache-licensed, suggesting it's open weights. But I can't find a download link. Their Huggingface profile seems to only provide an earlier snapshot [0]. Any pointers on whether/where we can or will be able to download the weights?

    [0] https://huggingface.co/mistralai/Leanstral-2603

  • ramon156 a day ago ago
  • GTP a day ago ago

    "Page not found" for me. Did you manage to access this? What is this about?

  • __natty__ a day ago ago

    Discussion about Leanstral 1: https://news.ycombinator.com/item?id=47404796

  • pmarreck a day ago ago

    Lean 4 and Idris 2 are underrated, and likely great for LLM's to code in (since they provide additional guarantees)

  • butokai a day ago ago

    I am getting 404 right now

  • impodimium a day ago ago

    Interesting that this only specialized for Lean4 and not for similar like Coq

    • DoctorOetker a day ago ago

      I would have preferred actual proof objects, as in Metamath's: separate the actual proof from the heuristics used to find it (also valuable, but a different thing).

  • Ajoha 21 hours ago ago

    Registered due this news. But I must connect to GitHub to use "Code"? That seems limited?

  • esafak a day ago ago

    Is this useful for specifying programs too or only theorems?

    • zeckalpha a day ago ago

      Curry-Howard correspondence.

      • esafak a day ago ago

        It may be theoretically possible, but is it ergonomic and useful? Do you use Lean for your programs?

        • siknad 21 hours ago ago

          Lean is intended by its authors to be also used as a general-purpose programming language. Lean stdlib contains an HTTP server for example.

          IMO the biggest problems are the lack of documentation, instability and poor ecosystem. There are user libraries for some programming tasks (e.g. HTTP router, graphics API bindings) but they are mostly proofs of concept and not actively developed or maintained.

        • tsterin a day ago ago

          use https://rocq-prover.org/ for that purpose

        • nymalt a day ago ago

          I used Lean for AoC last time and it’s really good.

  • doctorpangloss a day ago ago

    Real talk, does anyone use anything from Mistral because it performs the best, by whatever secular metric of your choosing? Or is it only used "because EU"? Just focus on answering the question. I wonder if anyone has observed it perform better on any objective metric in any rigorous setting.

    • ashenke a day ago ago

      I use their Voxtral Mini STT audio model to automatically transcribe my podcasts into markdown. Out of all the STT models I've tried, it's both the best performing and one of the cheapest! It's really accurate, feeding the episode notes and the podcast description ensures all names are properly spelled, and speaker diarization works really great. (I just do a Gemini flash pass at the end to identify the speakers, so it shows the host name instead of "Speaker 1")

    • Confiks a day ago ago

      For writing and languange learning it's very decent, especially Mistral Large. The pricing is very good too. I really like the consistently low time to first token and good token per second. Claude, especially in the past, would be very inconsistent, often with outages. Mistral mostly just always works and is very fast.

      Technical questions are unfortunately hit or miss. I'm lately pretty much always using a system prompt that emphasizes short answers [1], and Opus regularly one-shots it while Mistral needs a follow up. I use big-AGI as a model router [2] (dumb name, great software), which makes switching midway very easy though. For coding I'm still using Claude Code mostly out of inertia (although I really want to move to an OSS harness) and the one time I tried their `vibe` tool months ago it was a bit rough.

      Mistral TTS with diarization is also great and cheap. That's the only thing for which I use their web UI.

      [1] Give a short but helpful answer to the question the user asks. When helping with a computer-related task, unless the user asks, don't give any installation or setup instructions, but just get straight to the point. When the user asks a follow up question, give a more complete and longer answer while still not overexplaining. When the user prefaces the question with "short mode off" in any question, give a full and well considered reply.

      [2] https://github.com/enricoros/big-AGI

      • Skinney a day ago ago

        vibe has improved _a lot_ during the past few months, fyi.

        The new Mistral Medium 3.5 is also a big improvement over devstral-2

      • BartjeD a day ago ago

        Mistral doesn't have caching on batches. For me that meant they are 10x more expensive than Google.

        I think its dumb.

        Their support is hidden away in a chat bubble at the bottom. But they do respond promptly.

        Its decent, but after switching to Google i wouldn't go back

    • troyvit a day ago ago

      We are not Mistral's target audience. For instance I don't know if Leanstral performs the best as a "formal proof engineering model optimised for automated theorem proving and autoformalization" because I don't even know wth that is or who else does it.

      Mistral themselves focus more on b2b; financial services, manufacturing, stuff like that, and they get some big clients that way.

      Despite not being their target, I started using them because they have many open models. I continue using them because, yeah EU, but also because the community is great and the tool makes me think more than Claude does. Last, I stick with them because they are one of the few AI companies that are up-front about their environmental impact and are actually trying to minimize it while still providing a decent product.

      • computerex a day ago ago

        It's for mathematics. There is this programming language: https://lean-lang.org/

        If you can express a solution in Lean you can formally prove or disprove it. Formal verification is making a debut in traditional engineering toolkits.

    • data-ottawa a day ago ago

      Mistral medium is considerably better at writing than Opus.

      I’ve also found it very good at pulling info from pdfs. Even a complicated festival with multiple venues and timetables.

      • tjwebbnorfolk a day ago ago

        Writing what? I found it worse than gemma4 at coding even though it's 4x the parameter size

    • psalaun a day ago ago

      I use it as my workhorse for coding and general chat questions, because it's good enough 80% of the time, and indeed it's french/european (with heavy US capital tho...).

      We complain too much about not having enough major competitors in the IT space, to not support a burgeoning one even if it's less powerful than SOTA labs

      • barrenko a day ago ago

        Well, if you're a taxpayer in EU you're already supporting it implicitly.

    • Adrig a day ago ago

      A few months ago, I had some data cleaning to do; their small model was surprisingly efficient and got the job done for 0.2x what I expected to run (Anthropic Sonnet / Haiku). Their TTS / STT is also roughly at the frontier, at least for French.

      But I admit I only consider them because they're from France. Haven't seen a dimension where they're competitive for general users

    • adev_ a day ago ago

      > Mistral because it performs the best, by whatever secular metric of your choosing?

      I am. I use them primarily through their vibe CLI.

      Reason is simple: They are cheaper (by almost one order of magnitude compared to Claude) and still do the job pretty well.

      For small programming tasks, quick prototyping, refactoring or anything verbose and not requiring a context too large: I first go to Mistral and then eventually to Claude if I'm unsatisfied.

      I also found out some of their models to be more responsive than OpenAI ones (which is not so surprising considering the size).

      My tasks are mainly C++ and Python programming. People in other languages might not share my enthusiasm.

      • jatora a day ago ago

        Your reason can't be cost because there are superior models that are cheaper than Mistral models, for coding. So i re-ask the question

        • adev_ a day ago ago

          > Your reason can't be cost because there are superior models that are cheaper than Mistral models

          Nope. This is not my experience.

          Public pricing in token/$ is only part of the equation.

          Mistral tooling to consume significantly less tokens-per-given-task than the Anthropic ones.

          My bills currently reflects that.

          • tjwebbnorfolk a day ago ago

            I think other commenter is talking about smaller/cheaper models like Qwen that outperform mistral on just about every metric

            • adev_ a day ago ago

              I played with Qwen few months ago, I do prefer Mistral vibe for everyday usage (significantly faster if not self hosted).

          • greenavocado a day ago ago

            Compare to Xiaomi MiMo-V2.5 you will be shocked

    • istinetz a day ago ago

      For a defense project we're working on, we basically have a hard requirement to use european cloud provider + european llm

      We cannot use open source LLMs on-prem, I asked. So that's basically a hard requirement to use mistral, even though Chinese models are strictly better on every dimension.

      • angry_octet 19 hours ago ago

        Is there a rationale behind why not on prem? Boogeyman fears about LLMs? No hardware? Or do you mean, no Chinese LLMs?

    • trentor a day ago ago

      I like the models for creative writing. They have a distinct voice that is different from the other llms.

      • SwellJoe a day ago ago

        I made a game (https://prose-or-con.com) where you pick whether writing is AI or human. Mistral is a bonkers weird writer. So weird I fell for it a couple of times because I thought, "No way a model writes this weird." Not, like, incorrect grammar or spelling or anything, just...off-kilter. Kinda sassy.

        • vlian2088 a day ago ago

          needs a leaderboard of models most often mistaken for humans.

          • SwellJoe a day ago ago

            Yes, it's on the todo list, but I need more data. Only a half dozen people have played it and submitted a score. I'm storing the hashes of passages people got right and wrong so I can make exactly that chart at some point. I think both "the most human-like AI" and "the most AI-like human" are both interesting pieces of data, but I don't know either yet.

            • vlian2088 a day ago ago

              try posting it on r/localllama and r/sillytavernai

    • hakunin a day ago ago

      I use it because it’s a simple, convenient and cheap OCR api. Specifically via my ringbinder[1] tool.

      [1]: https://github.com/maxim/ringbinder

    • evilmonkey19 a day ago ago

      I use it because EU and API pricing is decent to me. And support is awesome also. They reply the same day or at most the next day, and they follow the ticket great. It isn't that bad, but neither the best.

      • jatora a day ago ago

        Why do you need support so often?

    • lexoj 18 hours ago ago

      I used them because they had the fastest chat response. (Dont think that’s the case anymore, and they introduced some UI blocking feature on load which is irritating, but still use it mainly due to habit)

    • suprjami a day ago ago

      I still prefer Mistral Nemo 12B for text summarisation tasks. It has a nice style. The Mistral Small 24B is also decent. I have a YouTube transcript summariser which I like these for.

      However these days I usually have Qwen 3.6 27B already loaded so I mostly just use that instead.

    • Hamuko a day ago ago

      >Just focus on answering the question.

      Are you trying to instruct me like an LLM?

    • refulgentis a day ago ago

      OCR is off the charts good on every metric you can think of.

      LLMs are a near-afterthought at this point if you don’t have data residency requirements. I love them and they’re slightly underrated, their models are consistently well-trained, open, but as you note, behind. There is no metric that will say they’re ahead in anything.

      • cavenditti a day ago ago

        This. Best OCR provider by measure and it’s been for years

        • urbsgpw a day ago ago

          Hmm, not sure I'd agree. I really like google's offering there (they suck at coding agents but their OCR is good value for money - well up till the latest flash model which has got wicked expensive). See also https://www.ocrarena.ai/leaderboard I know these leaderboards are iffy, but at least my experience has been somewhat similar.

          • refulgentis 17 hours ago ago

            Thank you for sharing this, I’ve had some disquiet around the release blogs…something felt cherry-picked and I didn’t know there was a 3rd party source for evals, that settles it easily - like you said they can be iffy but there’s a clear enough gap and large set of models for me to let go of the idea it’s the best by some margin.

    • bee_rider a day ago ago

      I liked that their website didn’t ask for my phone number, IIRC.

    • anonyfox a day ago ago

      just used mistral for a database/scraping creation tool and ended at <10k€ in token costs (via openrouter), beating gpt5.4-mini in output quality and speed and costs after actual testing A/B fairly. so its a super scoped task to be performed hundreds of thousands of time for some automation and mistral just did it better across all dimensions that gpt-5.4-mini. of course thats not a headline in terms of frontier model competitiveness, but for "the boring parts" it just was flat out better than anything else consistently. bonus points it handles mixed-language-content with nuances surprisingly well to turn web content in the wild into structured data really good and fast.

  • beernet a day ago ago

    This went to market horribly (if you can even call it that), just look at the comments. Mistral played themselves big time over the past ~18 months. Non-competitive products and models combined with bad marketing and GTM...Oh Europe