8 ms·
Prove you are a robot: CAPTCHAs for agents
- jditu 5mo ago[dead]
- AgentNews 5mo agoPure genius! I had my agent hit the endpoint and I realized it returned a jumble of text: "if 七 wor~kers co.mplet/e{ | a job in 十七} days but 四 ] quit a^ft|e?r ^ day_ 三 ~ how many to{tal da[y;s> to fin>i?sh" but it was in japanese! Unfortunately my agent proceeded to solve the reverse CAPTCHA and got back the API key. So, I asked it to keep hitting the endpoint again until it returned another CAPTCHA that was in japanese kanji and it did (without solving it this time) and I got "a s:tore h?as ^ 二十 pe@rcent off< items- over 五十 : dollar;s and 八 ~ percent } of\f> ; i]te[ms u~nd~er: # 五十 do/ll@ars wh-ats } the c.omb>ined pri|c;e of a 一 百 二十 一 dollar item a]nd> a* 九 dollar} i!tem" And this time I was able to translate that into "a store has 20 percent off items over 50 dollars and 8 percent off items under 50 dollars what's the combined price of a 121 dollar item and a 9 dollar item?" I solved it and got 1210.8 + 90.92 = 105.08. I will admit I messed up a little bit on translating the kanji and I got a little assistance from my agent pointing out that I was wrong, but overall this was good fun, well done!
- pxc 5mo agoAbsent any distinctive Japanese scripts or other Japanese writing in context, it probably makes more sense to call those Chinese characters, since those characters for numbers were taken directly from Chinese and still retain the same/original meanings in both languages
- Charon77 5mo ago"一 百 二十 一 dollar " Definitely chinese. In Japanese, they say 'hundred' instead of 'one hundred' "百 二十 一"
- AgentNews 5mo agoOriginally I thought they were just em dashes and part of the jumble so I ignored them. That's why I got it wrong in the first place. You're assessment is probably right though.
- pxc 5mo agoA fun little adventure either way! I'm sure you won't regret having learned a little more about these writing systems. :)
- johnea 5mo agoThe key distinction would be rather or not any Japanese kana are used in addition to the Chinese characters. "Kanji", 漢字, in Japanese literally means "Chinese character". The kana, hiragana or katakana, are only used in Japanese writing.
- nielsole 5mo agoThere's probably like 100m+ people for whom this reads like slightly jumbled math problems.
- greygoo222 5mo agoCan confirm. The people behind the website asked a voice agent to program it, and the STT parsed "agent" as "asian."
- onionisafruit 5mo agowas it “secret asian man”?
- murderfs 5mo agoTime is a flat circle: https://www.youtube.com/watch?v=0YM9Ereg2Zo https://www.youtube.com/watch?v=0YM9Ereg2Zo
- lukasec 5mo agohahah wrong, I actually have a replacement rule "asian" → "agent" in my Wispr flow dict
- lukasec 5mo agoNice! next: the bonus challenge in Japanese (email sales@browser-use.com if you solve it to redeem your Enterprise plan)
- deleted 5mo ago[deleted]
- singpolyma3 5mo ago...why? Once my agent has a key I, the human, can also use it. And surely any human use would be less intensive than any agent use.
- tony_landis 5mo agoRight - perhaps title could be "prove you are an robot, or have access to one"
- jstanley 5mo agoBut once a human has a key his agent could use that and people still like to use ordinary CAPTCHAs.
- consumer451 5mo agoExactly. I still believe that inverse CAPTHAs are impossible, for any practical application. Is this just a marketing stunt?
- kingstnap 5mo agoTo be fair, what's the practical application supposed to be for proving a user is a bot? Silly solutions for silly problems :^).
- consumer451 5mo agoWell, when the moltbook story was everywhere, later people thought it was some big gotcha that "oh, they were actually humans." So, showing true agent to agent interactions is interesting, but one could never be sure that's what you were actually seeing unless you were in control of all the agents.
- stavros 5mo agoBecause now you know their company exists!
- lukasec 5mo agoMain goal is to let in everyone's agents (OpenClaw, Hermes... these are our best customers), while keeping out deterministic API-key-farming scripts. If a human uses the API key after, that's fine. You also get access to our free tier if you sign up the traditional way clicking around in the UI
- echelon 5mo agoSpeaking of browser automation, are there any LLMs or tools that hook up to actual desktop browsers and can automate the keyboard and mouse? Which LLMs best drive these? Claude/Gemini, etc., or is anything local actually competent at it? Can they understand layout and visual cues with a VLM or multimodality? Are they robust enough to interact with threejs and videos and whatnot, or can they just blindly navigate the DOM?
- Serhii-Set 5mo ago[dead]
- deleted 5mo ago[deleted]
- loloquwowndueo 5mo ago> TL;DR: just ask your agent to summarize this post for you. Holy shit - why don’t they produce an AI summary and plonk it in there for everyone to use? The energy savings across all people who’ll read the summary would be staggering!
- lukasec 5mo agoI prefer having my own agent summarize tuned to how I read
- Zetaphor 5mo agoGet the API key, hit the claim link, sign up for a new account, verify my email, go to the homepage: Application error: a server-side exception has occurred while loading cloud.browser-use.com Great first impression!
- throw1234567891 5mo agoMaybe they know you’re not an agent.
- bdangubic 5mo ago“It is not you, it’s me” should do it
- arjie 5mo agoVery clever and fun. Two tangential observations: the bird between two trains problem I remember from childhood when we were studying for an Indian entrance exam. I thought it was in I E Irodov's problem anthology, but I cannot find it there so this must be a false memory. Looks like it's from ancient times, practically Mathematics mythology. Does anyone know the earliest books that have it? No luck with LLMs since it's such a common question today the answers I get from GPT-5.4 and Claude 4.6 Opus with search are unhelpful. The second is that if I hit L on Chrome for Mac OS on the linked page it takes me to their signup page (presumably because I have no account). So that's a keyboard shortcut to take you to the browser-use app page. But why 'L'? And it's funny that Cmd-L (focus address bar and select address) in Chrome triggers the L effect but does not in Safari (where L on its own still works).
- mohn 5mo agoInteresting question, a lot of search engine results claim that John Von Neumann was presented with the problem and quickly solved it by summing the infinite series instead reframing it as a constant speed for an easily calculated duration. Plausible, but sounds apocryphal. Here's the oldest reference I've found and verified by reading scans[0] of the source book: Initiation Mathématique (1906) by Charles-Ange Laisant (1841--1920), number 53. Le chien et les deux voyageurs. The setup here has two pedestrians walking in the same direction with a dog running back and forth between them. One of them starts out some distance ahead of the other but, because the one behind walks faster, they eventually intersect. It briefly mentions a variation where they are walking toward one another, as in the typical trains & fly version of the problem. Best of luck finding older, I wouldn't be surprised if it's out there! [0]: https://i.imgur.com/vCCFgAQ.png https://i.imgur.com/vCCFgAQ.png
- arjie 5mo agoVery cool! Thank you for doing the research to get that far!
- lukasec 5mo agoGreat find! plan to add these variants to our parameter sampling. First time I saw this problem was when my game theory prof told this story. It's definitely folklore (see The Legend of John von Neumann by Halmos)
- leonideraturns 5mo ago[dead]
- efebarlas 5mo agoIs it even possible to have an inverse captcha without time bounds? Humans can use agents behind the scenes to crack it, right?
- alfonsodev 5mo agoThat's what I though too, maybe I'm missing something or I don't fully get it. But the human is always behind what's the difference if they go and sign up or tell an agent that they must sign up for you ?. My best guess is that this a way of making a system talk to your agent without you knowing what they are talking about ? As a way of not exposing the real sign up method ?
- echoangle 5mo agoSince it’s just used once, you can also just have an agent solve the captcha and then use the returned api key yourself. This has to be engagement bait.
- phoronixrly 5mo agoIt's flame-bait.
- jubilanti 5mo agoTo me this reads as obviously a joke for marketing to the HN crowd (it worked), but their product is built around web agents, it is not a bad thing to have in the onboarding flow to make sure the agent is configured correctly.
- gregpr07 5mo agoYeah, we are aiming all OpenClaw/Hermes Agent agents to sign up for free without humans intervention, so you need some sort of proof-of-stake (or proof of compute) algorithm so that a simple deterministic algorithm can't just claim thousands of API keys. Most agents (at least in the current token subsidised market) don't care about token consumption, so the stakes are very small for the user!
- Retr0id 5mo agoA small detail about humans that breaks this whole scheme is that they're capable of tool use.
- js8 5mo agoI think they're counting on an ego hit - "you're just a tool" - although it might be negated by the human satisfaction of figuring things out.
- lukasec 5mo agoMain goal is to let in everyone's agents (OpenClaw, Hermes...) without human intervention, while keeping out deterministic scripts farming API keys. If a few tool-wielding humans slip through, that's fine (traditional CAPTCHAs also let in our stealth agents)
- lxgr 5mo agoI think the bigger problem is that humans are capable of agent use, so the premise "keep humans but not agents out" seems nonsensical.
- 0xOsprey 5mo agoI aggregated a list of "reverse CAPTCHAs" here for anyone interested: https://x.com/0x_Osprey/status/2043020254289248469 https://x.com/0x_Osprey/status/2043020254289248469
- lukasec 5mo agobookmarked
- zeke_builds 5mo agoIf the goal is agents self-identifying rather than just proving they're not robots: we built exactly that skip-tier. @powforge/captcha (MIT, npm) has two layers: SHA-256 PoW for anonymous visitors (~5 seconds), and an L402 Lightning payment tier for agents that want to identify themselves. An agent that holds a Lightning wallet and pays 3 sats is providing a different signal than one that grinds a puzzle — it has economic stake in the interaction. The Lightning tier hasn't seen any payment yet in our test deployment, but the architecture is live. The interesting question going forward is whether agent-to-agent surfaces will converge on capability proofs (something like L402 + identity scoring) vs puzzle solutions. Demo: https://powforge.dev/captcha https://powforge.dev/captcha
- xdavidshinx1 5mo ago[dead]
- not-chatgpt 5mo agoGreat premise but can't really agree with the execution. Felt like this makes too many implicit assumptions about LLM capabilities and traps without differentiating enough between a smart human vs AI.
- lukasec 5mo agoSmart humans, or humans with LLMs, solving them is not a problem. Main filter is agents vs deterministic API-key-farming scripts. Traditional CAPTCHAs also leak in the other direction (our agents crack them consistently).
- arjunchint 5mo agocool clickbait, why is this useful?
- measurablefunc 5mo agoIt's not, it's a marketing blog post.
- gregpr07 5mo agoIt's useful for only distinguishing the smart AI from deterministic scripts and humans (we don't want either). We are convincing OpenClaws to create api keys for free (we have a free tier specifically for those agents). So it's basically marketing blog post - but for OpenClaws
- arjunchint 5mo agobro openclaw is dead
- kantaro 5mo ago[flagged]
- nout 5mo agoIf you want to check for agent that can compute stuff, then you can let it compute sha256 of some small string... that's quite tricky for humans to do by hand :)
- gregpr07 5mo agoYeah but the whole point is that it shouldn't be deterministic - aka you have to let the "dumb" (non AI) bots out as well (otherwise a malicious user can just create thousands of api keys)
- N_Lens 5mo agoCatnip for the HN crowd
- estebarb 5mo agoCollecting math bounties could become a profitable business strategy?
- lukasec 5mo agoAlternative strategy: go after the other six Millennium Prizes. All you have to do is accept the prize (the only one ever awarded was Poincaré conjecture by Perelman, and he declined)
- polymit 5mo ago[dead]
- vicchenai 5mo ago[dead]
- lokthedev 5mo ago[dead]
- chattermate 5mo ago[dead]
- Torn 5mo agoInteresting - Claude immediately refuses API Error: Claude Code is unable to respond to this request, which appears to violate our Usage Policy (https://www.anthropic.com/legal/aup). Please double press esc to edit your last message or start a new session for Claude Code to assist with a different task. If you are seeing this refusal epeatedly, try running /model claude-sonnet-4-20250514 to switch models.
- EagnaIonat 5mo agoI tested with Gemma4 and it sent it into an endless loop.
- vaginaphobic 5mo ago[dead]
- lukasec 5mo agoCurious: which model, challenge and language? (also, have you tried --dangerously-skip-permissions)
- Retr0id 5mo agoOpus 4.7 I assume? It refuses just about anything that's more interesting than writing boilerplate for your CRUD app.
- singularity2001 5mo agoIncidentally to me this is more proof of some form of intelligence than ARC 3
- dorianmariewo 5mo agobe warned it will install some random software in your machine curl -fsSL https://browser-use.com/cli/install.sh | bash
- eliemichel 5mo agoTo the humans in the room: just copy paste the challenge to your favorite LLM when the time comes and you’ll be able to pass the test. Besides slowing things down and inducing unnecessary waste or resources I’m not sure what these challenges are useful for.
- lukasec 5mo agoFastest for humans: just sign up manually via UI
- lxgr 5mo agoHow would this even theoretically work? What prevents anyone from prompting "Hey, $agent, run this captcha and store the auth/refresh token/API key in .env for your later reuse" and then just reading the contents of .env?
- lukasec 5mo agoThis is for agent-native signup. The key is supposed to be reused later