What is Policy Testing?

Policies are code. They define logic, have edge cases, and can contain bugs. A policy that accidentally blocks a critical tool call is a production incident. A policy that fails to block a dangerous operation is a security incident. Testing catches both before they reach production.

Policy testing differs from policy dry-run in scope and timing. Dry-run observes policy behaviour against live traffic — it tells you what would happen with real tool calls. Testing validates policy behaviour against synthetic test cases — it tells you whether specific scenarios produce the expected outcome. Testing happens before deployment; dry-run happens during staged rollout. Both are essential.

Effective policy tests cover three categories: positive tests (verify that permitted operations are allowed), negative tests (verify that restricted operations are denied), and boundary tests (verify behaviour at condition thresholds, e.g. exactly at the payment limit). A policy without tests is a policy you cannot confidently change — any modification might break existing behaviour in ways you discover only when agents fail in production.

PolicyLayer validates every policy at the point it is saved in the dashboard — the JSON document is checked against the policy schema before it can take effect, catching malformed rules early. The visual policy builder makes expected behaviour explicit: each tool carries a clear Allow, Deny, Hide or Custom decision, so reviewers can confirm outcomes tool by tool before saving. To exercise a policy end to end, teams start from "default": "deny", issue representative tool calls through the gateway, and check that the recorded decisions match expectations. The Raw JSON view exposes the exact document under test, keeping review straightforward.