OpenRouter launches Fusion API, combining benefits of Fable 5 & GPT 5.5, at half the price

OpenRouter has launched Fusion, a compound model API that combines outputs from multiple AI models in parallel to produce higher-quality responses. On OpenRouter's internal benchmark, its top Fusion configuration, combining Claude Fable 5, now off the table for most users worldwide, and GPT-5.5, achieved highest score. Fusion achieved Fable-level intelligence at half the price, said OpenRouter.