Your prompt can ask a model what it is. Your production system should not trust the answer. A model can say it is GPT, Claude, Gemini, Llama, Qwen, or anything else. That does not prove what is behind the endpoint. A gateway can route requests silently. A provider can change a default model. A fallback can trigger during an outage. A proxy can strip metadata. A fine-tune can imitate another model's tone. Even honest teams can ship the wrong route because an environment variable, tenant flag...