OpenAI seed and system_fingerprint for Reproducible Outputs

Chat Completions are non-deterministic by default. To receive mostly deterministic outputs across API calls, OpenAI provides the integer seed parameter and the system_fingerprint response field: pass the exact same seed, prompt, and temperature across requests, and monitor system_fingerprint to track backend system changes.

API Config: seed=1042, temperature=0.0 Audit Rule: Log response.system_fingerprint on every test run to verify backend configuration stability across regression evaluations.