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lukasec

38 karma · joined March 31, 2025

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lukasec··on Prove you are a robot: CAPTCHAs for agents
This is for agent-native signup. The key is supposed to be reused later
lukasec··on Prove you are a robot: CAPTCHAs for agents
By "deterministic" I mean "non-LLM". An LLM can still farm keys, but at a per-attempt inference cost
lukasec··on Prove you are a robot: CAPTCHAs for agents
Fastest for humans: just sign up manually via UI
lukasec··on Prove you are a robot: CAPTCHAs for agents
We do have time bounds. For our purposes, a human using an agent is fine. Our main goal is to let in everyone's agents (OpenClaw, Hermes...) and prevent deterministic API-key-farming scripts.
lukasec··on Prove you are a robot: CAPTCHAs for agents
Main 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)

lukasec··on Prove you are a robot: CAPTCHAs for agents
Curious: which model, challenge and language? (also, have you tried --dangerously-skip-permissions)
lukasec··on Prove you are a robot: CAPTCHAs for agents
Nice! next: the bonus challenge in Japanese (email sales@browser-use.com if you solve it to redeem your Enterprise plan)
lukasec··on Prove you are a robot: CAPTCHAs for agents
hahah wrong, I actually have a replacement rule "asian" → "agent" in my Wispr flow dict
lukasec··on Prove you are a robot: CAPTCHAs for agents
Great 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)
lukasec··on Prove you are a robot: CAPTCHAs for agents
Smart 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).
lukasec··on Prove you are a robot: CAPTCHAs for agents
bookmarked
lukasec··on Prove you are a robot: CAPTCHAs for agents
Alternative 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)
lukasec··on Prove you are a robot: CAPTCHAs for agents
Main 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

lukasec··on Prove you are a robot: CAPTCHAs for agents
I prefer having my own agent summarize tuned to how I read