Function buildImagesUsage

packages/openai-base/src/usage.ts:129–159

(
  usage: OpenAI.Images.ImagesResponse['usage'] | undefined | null,
)

 * omit the field rather than emit zeroed totals.
 */
export function buildImagesUsage(
  usage: OpenAI.Images.ImagesResponse['usage'] | undefined | null,
): TokenUsage | undefined {
  if (!usage) return undefined

  const result = buildBaseUsage({
    promptTokens: usage.input_tokens || 0,
    completionTokens: usage.output_tokens || 0,
    totalTokens: usage.total_tokens || 0,
  })

  // The SDK types input_tokens_details (and its numeric fields) as required, but
  // real responses — e.g. from DALL·E or other non-token-billed models — can
  // omit them, so treat the breakdown as optional.
  const inputDetails = usage.input_tokens_details as
    | { text_tokens?: number; image_tokens?: number }
    | undefined
  const promptTokensDetails = {
    ...(inputDetails?.text_tokens
      ? { textTokens: inputDetails.text_tokens }
      : {}),
    ...(inputDetails?.image_tokens
      ? { imageTokens: inputDetails.image_tokens }
      : {}),
  }
  if (Object.keys(promptTokensDetails).length > 0) {
    result.promptTokensDetails = promptTokensDetails
  }

  return result
}