An anonymous image model called mona-lisa-1 turned up on Arena today, and several people independently flagged it as OpenAI's within hours. @AiBattle_ posted the first sighting this morning, having run the outputs through OpenAI's own verification tool and got a hit. That matters more than it sounds: OpenAI watermarks its images with SynthID via a partnership with Google, and the checker looks specifically for a watermark originating from OpenAI. One commenter noted that the other accounts passing the story around had left that detail out.

So the provenance is reasonably solid. What the model actually is stays wide open, and the early reads are strikingly muted. @synthwavedd ran comparisons through the day and called it a slight improvement in realism and noise over GPT-Image 2, not a big jump. @WolfRiccardo posted raw outputs two hours earlier and framed it as rumour. On Reddit the verdict was that "it doesn't seem deeply different".

Blind arena testing won't settle it. Everyone is running different prompts with no seed control and no fixed comparison set. @synthwavedd reads the "-1" suffix as a promise of further checkpoints, which fits April, when three tape-themed codenames ran on Arena before shipping as GPT-Image 2 on the 21st.

No outlet has covered mona-lisa-1. For now it's a few thousand views on X and a Reddit thread that can't tell whether it's looking at anything new.

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