OpenAI claims GPT-5.6 Sol beats Opus 5 on ARC-AGI-3 with its latest API and two additional settings

OpenAI counters Anthropic's ARC-AGI-3 record: GPT-5.6 Sol scores 38.3 percent, but only with its own API features instead of the official test setup, where the model landed at 7.8 percent. ARC Prize claims its test environment is provider-neutral, but may have used an outdated API that skewed the comparison with Opus 5.