Use when the user asks to "generate (test) scenarios", "generate evaluators", "create an evaluator", "create evals", "create a scenario", "write a test scenario", "design a test case", "test my agent", "build eval coverage", "plan a test suite", "create red team tests", "set up test profiles", "configure conditional actions", "build a deterministic test", "design an IVR test", "write a unit test for a voice agent", "build a regression test", "scripted scenario", "structured evaluator", or "run evals". Also for CHANGING existing evaluators — "update an evaluator", "improve my evals", "make these evaluators stricter", "add a DTMF step", "fix the expected outcome", "attach metrics to these" — and for debugging how the testing agent speaks: "why did it read the number as a word", "make it spell digits", "wrong language". Covers evaluator design and review, coverage, test profiles, mock-tool data, conditional actions, and red-team / edge-case practice.