OpenAI Cuts GPT-5.6 Luna Prices 80% After Self-Optimization

GPT-5.6 Luna now costs 20¢ per million input tokens and $1.20 per million output tokens after the 80% price cut. OpenAI says GPT-5.6 Soul, running in Codex, rewrote GPU kernels and improved speculative decoding, cutting serving costs 20% and lifting token-generation efficiency 15%. Mid-tier Terra got a 20% cut; Soul gained 2.5x speed for 2x cost.