Bill - Narev Docs

Connect model usage to the customer who generated it. AI-billing captures usage in Vercel AI SDK calls and sends normalized events to billing destinations such as Polar, Stripe, Lago, and OpenMeter.

Capture your first event

Use Node.js 22 or later. Install compatible packages in your Node.js project:

npm install ai@^6 @ai-sdk/provider@^3 @ai-sdk/gateway@^3 @ai-billing/gateway@^0.2 @ai-billing/core@^0.1.6
npm install --save-dev tsx

Set AI_GATEWAY_API_KEY in your server environment. Gateway inference can incur charges. Create billing.ts:

import { generateText, wrapLanguageModel } from 'ai';
import { createGateway } from '@ai-sdk/gateway';
import { createGatewayV3Middleware } from '@ai-billing/gateway';
import { consoleDestination } from '@ai-billing/core';

const apiKey = process.env.AI_GATEWAY_API_KEY;
if (!apiKey) throw new Error('Set AI_GATEWAY_API_KEY');

const gateway = createGateway({ apiKey });
const model = wrapLanguageModel({
  model: gateway('openai/gpt-4o'),
  middleware: createGatewayV3Middleware({
    destinations: [consoleDestination()],
  }),
});

await generateText({ model, prompt: 'Say hello in one sentence.' });

Run npx tsx billing.ts and inspect the console billing event for usage and cost. This meters a request; it does not charge a customer. Next, configure a billing destination and Customer Tagging from authenticated server state.

Learn more

Explore AI-billing and follow the quickstart for tagging and pricing sources. Choose a billing integration when you are ready to send customer-attributed events.

Last modified on October 30, 2026