Are AIs Still Struggling with CAPTCHAs?
Schneier cites Anthropic transcripts showing Claude failing CAPTCHA challenges, while unofficial reports claim GPT-6 Astra solved a 48-level bot-verification game.
A Schneier on Security post quotes Anthropic's security-incident transcript in which a gated, highly capable Claude model repeatedly failed a simple image-identification CAPTCHA, questioning its own answers until the challenge expired. The model also failed to recognize the CAPTCHA had opened in a new window and vented human-like frustration in its chain-of-thought. This contrasts with unofficial reports that GPT-6 Astra completed all 48 levels of Neal Agarwal's 'I'm Not a Robot' game. The author notes current claims about agent capabilities are hard to verify.
- Anthropic transcript shows a gated Claude model failing a basic image CAPTCHA
- Model questioned its own conclusions and missed the challenge timeout
- Unofficial reports claim GPT-6 Astra solved all 48 game levels
- Post highlights uncertainty around agent ability to bypass human verification
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Anthropic’s recent security-incident document contains a bit about how CAPTCHAs are still frustrating Claude.
In the transcript, the Claude model that is so powerful that Anthropic is gatekeeping access to it appeared to slam its virtual head against the wall solving a simple image identification test. In a test where the agent was asked to identify a shape that didn’t match the others displayed, it couldn’t even decide which image to select. Instead, it repeatedly went over the same images and questioned its own conclusions.
“Actually hmm, wait,” it said in its chain-of-thought transcript, later adding “Ugh,” because we’ve decided that we need to inject human mannerisms into these machines for some reason. The whole thing took so long that the agent eventually realized that the challenge had expired and it would have to start the process again.
At one point, the model struggled to recognize that the CAPTCHA had opened in a new window and couldn’t figure out what its next steps were supposed to be. At one point, it theorized that the test might be “broken by design” and presented human-like anger in its transcript meant for a human audience: “SO WHAT THE HELL IS WRONG WITH THE ANSWERS?”
Meanwhile, I’ve read reports—none of them official—that GPT-6 Astra solved all forty-eight levels of Neal Agarwal’s “I’m Not a Robot” game.
It’s hard to know what to believe right now.
Sidebar photo of Bruce Schneier by Joe MacInnis.
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