Meta claims Watermelon matches GPT-5.5, plans open-source

Meta's upcoming frontier model, codenamed Watermelon, has caught up with OpenAI's GPT-5.5 on internal benchmarks, according to superintelligence chief Alexandr Wang. The model is still training and uses an order of magnitude more compute than Avocado. Meta also confirmed it will release an open-source model in the future.