GPT-2?

Summary from the TLDR AI newsletter

A mysterious AI model named gpt2-chatbot, displaying capabilities akin to GPT-4.5, has emerged on lmsys.org, prompting speculation of it being an unofficial OpenAI test for their next iteration. Key identifiers such as response quality, OpenAI-specific traits, and rate limits suggest a high level of sophistication, potentially hinting at a discreet benchmarking initiative by OpenAI. Investigations and discussions around gpt2-chatbot's origins and capabilities are ongoing in the AI community.