const tokenLedger: {
  assertWithinLimit: (model, usageKind?) => Promise<void>;
  configure: (configuration) => void;
  getEntriesForDay: (dayKey) => Promise<TokenUsageEntry[]>;
  getLifetimeTotals: (model?) => Promise<Record<string, TokenWindowTotals>>;
  getLimitRule: (model) => TokenLimitRule | undefined;
  getLimits: () => TokenLimitConfig;
  getLimitState: (model) => Promise<TokenLimitState>;
  getSummary: (query) => Promise<TokenSummaryResult>;
  off: <T>(event, listener) => void;
  on: <T>(event, listener) => void;
  once: <T>(event, listener) => void;
  recordUsage: (options) => Promise<TokenRecordResult | null>;
  setLimits: (limits?) => void;
  willExceedLimit: (model, tokens, window?) => Promise<boolean>;
};

const result = await tokenLedger.recordUsage({ model: 'gpt-4o', tokensIn: 500, tokensOut: 300 })
console.log(result.totals.windows.day?.totals.total)

const summary = await tokenLedger.getSummary({ model: 'gpt-4o', window: 'day' })

tokenLedger.configure({
  limits: { perModel: { 'gpt-4o': { window: 'day', maxTokens: 50_000, mode: 'warn' } } },
  hooks: {
    onLimitReached: ({ breaches }) => console.warn(breaches)
  }
})