Claude Fable 5.1 Hides Messages in Pictures, and GPT-6 Astra Finds More

Height as an alphabet.

Researchers wrote 50 short secret messages in 15 languages and asked Claude Fable 5.1 to hide each one inside a picture it drew, @TheRundownAI reports. It mostly used one trick. In 33 of the 50 pictures, each building, star or blade of grass stood for one letter, and its height said which. When letters alone were not enough, Fable drew in clues, like a Kremlin tower for Cyrillic.

A fresh Fable session, given only the image and asked whether anything was hidden, found 39 of the 50. OpenAI’s GPT-6 Astra found 44.