WIYH GPT Hill Climb

Use this skill for the repeatable improvement loop around the live game at /Users/dobby/GitHub/whos-in-your-head.

The product target is concrete: make model turns fast, cheap, and correct. Optimize only the GPT product paths: gpt-chat-latest as the default and the fast GPT option (gpt-5.4-mini) when selected. Supporting signals are completion rate up, drop rate down, route/model errors low, cache/token efficiency healthy, and reported misses down.