Which model actually writes better TypeScript, and does it matter enough to change what you reach for? I ran Claude Fable 5 and GPT-4o through the same set of TypeScript generation tasks to find out, and the answer is more useful than a leaderboard number: each model has a different failure mode, and which one bites you depends on what you are building. I do a fair amount of AI systems architecture work, and picking the right model for codegen inside a pipeline is a decision that compounds....