OpenAI tests unannounced image generation model mona-lisa-1

The image generator mona-lisa-1 appeared on the Arena platform on August 9, 2026, with its OpenAI ownership confirmed via SynthID watermark and C2PA metadata.

Compiled by Sergey KostenchukPublished 2026-08-11Updated 2026-09-18

2026-08-11 Multimodal OpenAI

🎨 OpenAI tests mona-lisa-1

Since August 9, the unannounced image generator mona-lisa-1 has appeared on Arena (chat.lmsys.org). SynthID watermark and C2PA metadata confirm OpenAI ownership. Testers note better handling of complex instructions and photorealism — but noise in textures and text issues remain.

🌍 Signal of an active development phase from OpenAI — reducing manual retouching of images in commercial pipelines.

👤 No API and API map yet. If the model is confirmed — the GPT Image 2 update will come to ChatGPT Plus and API in the coming weeks.

Source 1: https://x.com/AiBattle_/status/2086405404368503240

Source 2: https://wavespeed.ai/blog/ai-news/mona-lisa-1-openai-image-model-arena/

Sources