/**
 * The tokens a chat completion used, as the model reported them.
 */
export interface ChatUsage {
    /** Tokens in the prompt. */
    prompt_tokens: number;
    /** Tokens generated, reasoning tokens included. */
    completion_tokens: number;
    /** Of `completion_tokens`, how many the model spent reasoning; null when the model reports none. */
    reasoning_tokens?: (number | null) | undefined;
    /** True when the model reported no usage and the counts are estimated from the request and response bytes. */
    estimated: boolean;
}