Use when the user asks to "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", "write a conditional action evaluator", "build a deterministic test", "design an IVR test", "IVR navigation test", "write a unit test for a voice agent", "build a regression test", "scripted scenario", "scripted voice test", "structured evaluator", "exact flow test", "sequential conditions", "fixed sequence test", or "run evals". Also for debugging how the testing agent speaks — "why did it read the number as a word", "make it spell digits", "wrong language" — via scenario_language, personality, and XML tags. Covers evaluator design, coverage strategy, test profiles, mock-tool data, conditional actions (deterministic / unit test / regression / IVR flows), and workflow / red-team / edge-case best practices.