Remember ultrathink? The magic keyword that unlocked Claude’s maximum reasoning power? It’s deprecated. But here’s what replaced it — and a hidden trick to get twice the thinking budget on 64K output models. The Old Way: The ultrathink Keyword For months, ultrathink was the magic word. Add it to your prompt, get 31,999 thinking tokens. Hacker News threads debated its effectiveness. Power users swore by the “Opus + Ultrathink + Plan Mode” combo. Under the hood, Claude Code detected the keyword an...