TanStack AI

npm install @tanstack/react-ai @ai-sdk/openai

// lib/opendunes.ts
import { createOpenAI } from "@ai-sdk/openai";

export const opendunes = createOpenAI({
  baseURL: "https://opendunes.com/api/v1",
  apiKey: process.env.OPENDUNES_API_KEY, // server-side only
});

// app/actions/chat.ts
"use server";

import { streamText } from "ai";
import { createStreamableValue } from "ai/rsc";
import { opendunes } from "@/lib/opendunes";

export async function chat(userMessage: string) {
  const stream = createStreamableValue("");

  (async () => {
    const { textStream } = streamText({
      model: opendunes("anthropic/claude-sonnet-5"),
      messages: [{ role: "user", content: userMessage }],
    });

    for await (const chunk of textStream) {
      stream.update(chunk);
    }

    stream.done();
  })();

  return { output: stream.value };
}

// app/components/Chat.tsx
"use client";

import { useState, useTransition } from "react";
import { readStreamableValue } from "ai/rsc";
import { chat } from "@/app/actions/chat";

export function Chat() {
  const [response, setResponse] = useState("");
  const [input, setInput] = useState("");
  const [isPending, startTransition] = useTransition();

  const handleSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    setResponse("");

    startTransition(async () => {
      const { output } = await chat(input);
      for await (const chunk of readStreamableValue(output)) {
        setResponse((prev) => prev + (chunk ?? ""));
      }
    });
  };

  return (
    <form onSubmit={handleSubmit}>
      <input
        value={input}
        onChange={(e) => setInput(e.target.value)}
        placeholder="Ask something..."
      />
      <button type="submit" disabled={isPending}>
        {isPending ? "Thinking…" : "Send"}
      </button>
      {response && <p>{response}</p>}
    </form>
  );
}

// Fast, lower cost
opendunes("meta-llama/llama-4-maverick")

// High quality, higher cost
opendunes("anthropic/claude-opus-4.8")

# .env.local
OPENDUNES_API_KEY=sk-your-key-here