Kimi K3 vs Claude Fable 5 vs GPT-5.6 vs Grok 4.5: Who Actually Wins?

Three AI giants spent thirty days trading the flagship crown — then Moonshot AI crashed the party. Kimi K3 launched today: 2.8 trillion parameters, the largest open-weight model ever, and it lands within half a point of GPT-5.6 Sol on Terminal-Bench at half the price. In 11 days the full weights go public, and the price of frontier AI can drop to whatever your own hardware costs. I put it against Claude Fable 5, GPT-5.6, and Grok 4.5 honestly: where K3 genuinely wins (best agentic browsing score ever published, and the only frontier option where your data never leaves your own servers), where it still loses (Fable 5's grip on real repo work is untouched), and the question everyone asks about a Chinese model — is your data safe? The answer depends entirely on how you run it, and I break down exactly that. The cost-per-task chart near the end is the one every closed AI lab stared at today. Closed models sell the ceiling. Open models raise the floor. Which side are you paying for? Tell me in the comments. TIMESTAMPS: 0:00 The fourth flagship 0:01 THE PARTY CRASHER 0:45 THE THESIS 0:54 The crasher 0:55 THE BIGGEST OPEN MODEL EVER 1:36 THE AGENT NUMBERS 2:15 The new leaderboard 2:17 HALF A POINT FROM THE CROWN 2:49 IS YOUR DATA SAFE? 3:28 THE REPO, STILL CLAUDE'S 4:09 The money 4:10 THE NEW PRICE LADDER 4:46 FIVE POINTS, TRIPLE THE PRICE 5:26 THE RULE 5:35 WHICH ONE TO GET 6:14 END #KimiK3 #ClaudeFable5 #GPT56 #AI