UsageMetadata

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/UsageMetadata",
  "title": "UsageMetadata",
  "type": "object",
  "description": "Metadata on the generation request's token usage.",
  "properties": {
    "promptTokenCount": {
      "type": "integer",
      "format": "int32",
      "description": "Number of tokens in the prompt."
    },
    "candidatesTokenCount": {
      "type": "integer",
      "format": "int32",
      "description": "Total number of tokens across all the generated response candidates."
    },
    "totalTokenCount": {
      "type": "integer",
      "format": "int32",
      "description": "Total token count for the generation request (prompt + response candidates)."
    },
    "cachedContentTokenCount": {
      "type": "integer",
      "format": "int32",
      "description": "Number of tokens in the cached part of the prompt (the cached content)."
    }
  }
}