Metric Calculation Engine

A library skill that performs goal-progress calculations with deterministic (pure-function) logic instead of leaving them to LLM guesswork. It is compatible with the goal-card-v2 schema and reusable for the FAZ 0 (Gap Check) step of automator agents.

What it does

For each goal it runs six operations:

• delta — the distance of the latest measurement from the target (according to the maximize / minimize / maintain direction).
• trend — the tendency of the last N points (least-squares slope; min 3, ideally 5+ points).
• target_check — checks whether the target has been reached.
• regression — whether the last 2-3 measurements run counter to the target direction (regression detection).
• pareto — comparing two actions across multiple goals and finding the Pareto-dominated one.
• exploration_budget — the percentage of the remaining exploration (explore) quota.

When to use

When an agent needs metric delta calculation, trend analysis, a target-reached check, regression detection, or a multi-goal Pareto comparison. It is designed to avoid the "make the LLM do the math" anti-pattern.

Output

One row per goal: structured JSON containing the delta, target_reached, progress_pct, trend slope + direction + confidence level, regression flag, and exploration_budget fields. In this example, the 7 goals of an ad campaign optimization (CPC, conversion rate, budget protection, ROAS, CTR, acquisition cost, bounce rate) are computed — regression is detected in ROAS and acquisition cost.