type ResponsesLiteModel = string | { id: string } | undefined; export function supportsResponsesLiteModel(model: ResponsesLiteModel): boolean { const modelId = typeof model === "string" ? model : model?.id; if (!modelId) return false; const id = modelId.includes("/") ? (modelId.split("/").pop() ?? modelId) : modelId; return /^gpt-5\.6-(?:luna|terra|sol)$/.test(id.toLowerCase()); }