Use Meliai with the Vercel AI SDK for Next.js Apps

The Vercel AI SDK’s OpenAI provider supports a custom baseURL, so you can route all inference through Meliai without changing your application logic. Create a single provider instance pointed at https://api.meliai.ai/v1, then use it anywhere you would normally reference an OpenAI model — streaming route handlers, server actions, generateText, generateObject, and more.

Install the AI SDK

Add the core AI SDK package and the OpenAI provider to your project.

npm install ai @ai-sdk/openai

Create a Meliai provider

Use createOpenAI from @ai-sdk/openai to build a reusable provider configured for Meliai. Export it from a shared module so you can import it across your app.

import { createOpenAI } from "@ai-sdk/openai";

const meliai = createOpenAI({
  apiKey: process.env.MELIAI_API_KEY,
  baseURL: "https://api.meliai.ai/v1",
});

Use in a Next.js Route Handler

Pass the Meliai provider and a model ID to streamText inside an App Router route handler. The response is a standard streaming data stream compatible with the useChat and useCompletion hooks on the client.

import { streamText } from "ai";
import { createOpenAI } from "@ai-sdk/openai";

const meliai = createOpenAI({
  apiKey: process.env.MELIAI_API_KEY!,
  baseURL: "https://api.meliai.ai/v1",
});

export async function POST(req: Request) {
  const { messages } = await req.json();

  const result = streamText({
    model: meliai("<MODEL_ID>"),
    messages,
  });

  return result.toDataStreamResponse();
}

Add your environment variable

Add your Meliai API key to your local environment file so Next.js can read it at runtime.

MELIAI_API_KEY=sk-mel-...

Add MELIAI_API_KEY to your Vercel project’s environment variables before deploying. Go to Project Settings → Environment Variables in the Vercel dashboard and add the key for your production, preview, and development environments.

Append a routing suffix to the model ID for provider selection — for example, meliai("<MODEL_ID>:eco") routes to the lowest-carbon available provider, and meliai("<MODEL_ID>:speed") prioritises the fastest response.