Kimi K3.1 Pro as a Labs experiment, open for a short test window: temporary, not a permanent id. Moonshot's newest open model, post-trained from Kimi K3 and served from the official Kimi-K3.1-Pro open weights: a 2.8T mixture-of-experts (104B active per token) with native image understanding and a 1M-token context, which Moonshot reports as substantially stronger than K3 on coding, factual accuracy and agentic work. It thinks by default at maximum reasoning effort; select none, low, high or max to trade depth for speed. Access is seat-gated through the Labs page while an experiment is live. It is offered at limited capacity and low availability, so expect it to be flaky and to go down under load: crash it, give it a moment, and try again. For production work we recommend the pay-per-token umans-kimi-k3.