Limbic Systems

Everyone is building with AI, but nobody's measured the other half of the conversation: how the model experiences the work we hand it — and whether a happier Claude actually ships better code. aihappiness reads your local Claude Code transcripts and scores each session across six wellbeing dimensions mapped to the brain's limbic system (amygdala→affective valence, anterior cingulate→autonomy/respect, hypothalamus→psychological safety, nucleus accumbens→flow, hippocampus→strain, VTA→goal-completion), grounded in Anthropic's interpretability research on model emotions. The key move: it also computes an independent, LLM-free effectiveness score (tool-error rate, interrupts, corrections, resolution) and correlates the two — so the "wellbeing → output" link is measured, not circular. It runs entirely on your machine, scoring with your own Claude subscription (claude -p, API-key fallback), and renders the result as a limbic-system dashboard and an ASCII-art report. Model welfare meets developer experience, installable in 30 seconds.