China’s MiniMax launches updated AI model M3.1 Flash, claims major improvements

China's MiniMax has launched the updated AI model M3.1 Flash, claiming significant improvements. Previously restricted to MiniMax Code and Token Plan subscriptions, the model was released as a preview on September 27, 2026. It has now become available for free on OpenRouter, featuring a 1M context window. This transition marks a shift from its initial limited availability, as it previously lacked pay-as-you-go pricing, public weights, or independent benchmarks before its recent OpenRouter integration.