/experiment — Metric-Driven Optimization Loop

Identity

/experiment is an automated optimization loop with a scalar fitness function. It takes a hypothesis, runs isolated experiments in git worktrees, measures results with a metric command, and keeps improvements or discards failures. Think of it as automated A/B testing for code changes.

Inputs

The user provides three things:

1. scope: Files to modify (glob pattern, e.g., "src/api/**/*.ts")
2. metric: Shell command that outputs a single number (e.g., npm run build 2>&1 | tail -1 | grep -oP '\d+')
3. budget: Iteration cap (default: 5) or time cap (e.g., "10 minutes")

If any input is missing, ask for it. The metric MUST output a single number to stdout.

Protocol