Microsoft's Phi 4 responds to a simple "Hi" with 56 thoughts

Microsoft's Phi 4 model generates 56 sentences before responding to "Hi", developer Simon Willison found. This behavior, known as "overthinking", was confirmed by Microsoft's Dimitris Papailiopoulos, who says it's problematic for simple tasks but intentional for complex ones. He plans to address the issue. Microsoft released the open Phi 4 reasoning models in early May.

Phi 4's reasoning process shown in screenshot by Simon Willison.