Give any rule an active date window and a policy change turns itself on and off. Schedule a price change weeks ahead, retire a promotion at midnight, and prove both work with a simulated run date in your tests.
The new Verify tab reads your RuleSet without running it and tells you what is wrong: rules that can never fire, rules that duplicate each other, two rules fighting over the same value, keys nothing supplies, and input combinations no rule covers.
Most engines tell you the result. The inference trace tells you the reasoning — every firing in order, a green/red condition tree with the actual values, every context change, and a plain-language explanation on demand.
Edit the inputs and hit Compare. AI Rule Engine runs your RuleSet twice in the sandbox and shows exactly which rules and conclusions changed — each traced back to the input that moved it. No metered run, no side effects, nothing in your history.
Why the expression language has no now() or random(), why re-fires key off real value changes, why AI results are remembered for unchanged inputs, and why an inference cascade still meters as one run. Determinism is what makes the rest trustworthy.