Unit tests per agent with mocked tool responses and deterministic LLM outputs.

Unit tests per agent with mocked tool responses and deterministic LLM outputs. Integration tests: full pipeline on golden test cases, compare final output to expected. Per-agent metrics: task completion rate, tool call accuracy, hallucination rate. System-level: end-to-end latency, cost per run, human escalation rate. Use OTel traces to replay failed runs for debugging. Gate deploys on regression test pass rates.