GPT-6 Luna is one of OpenAI's GPT-6 models, launched in September 2026 at $0.10 per million input tokens and $0.50 per million output tokens, making it among OpenAI's cheapest models. Recent coverage examined its poor confidence calibration in OpenAI's new Decisions API, where it was right only 68% of the time when claiming 99% confidence, and its second-place finish in a Pac-Man decision-model benchmark. Inception's Mercury 3 also claims to run 4–8x faster than GPT-6 Luna, though no independent tests exist yet.
Inception claims Mercury 3 diffusion model far outpaces rivalsInception released Mercury 3, which it calls the most capable diffusion language model so far. The company claims it runs four to eight times faster than GPT-6 Luna and Claude Haiku 5.5 and wins eight of 12 benchmarks, but no independent tests exist yet.
Mercury 3 launches as most capable diffusion LLM, running 4–8x fasterMercury 3, a new diffusion-based LLM, claims to outperform GPT-6 Luna and Claude Haiku 5.5 on several benchmarks while running 4–8x faster at 1,068 tokens per second. It is over 40x larger than Mercury 1 and supports 1M-token context, priced at $0.20 per million input and $0.70 per million output tokens, with a 50% launch discount. The maker says scaling laws hold for diffusion too, and early partners use it for voice support, tutoring and web navigation.
AI decision models play Pac-Man: jev 1.13 tops leaderboardA Reddit user benchmarked six decision models by having them play Pac-Man in real time and published an open-source leaderboard. jev 1.13 led with an average score of 2,750, followed by GPT-6 Luna and Clef Flash. Users can also play as Pac-Man against model-controlled ghosts.
OpenAI Decisions API Confidence UnreliableTests show GPT-6 Luna, behind OpenAI's new Decisions API, is poorly calibrated: when it claimed 99% confidence across 3,600 reasoning problems, it was right only 68% of the time, highlighting AI confidence-calibration problems.
OpenAI and Anthropic Cut AI Model Prices, Escalating Price-Performance RaceOpenAI released GPT-6 Sol and Luna with 50% lower costs than predecessors. Anthropic launched Claude Opus 5.5, priced 20% below Opus 5 and performing near top-tier models. Analysts say the race is shifting to efficiency.
Claude Opus 5.5 and GPT-6 Launch Spark Price WarAnthropic released Claude Opus 5.5, and about an hour later OpenAI launched GPT-6 Sol and GPT-6 Luna at roughly half the price of their GPT-5.6 equivalents. GPT-6 Luna costs just $0.10/M input and $0.50/M output, among OpenAI's cheapest models, intensifying the price war.
The A.I. Daily