const client = new SandstoneClient({
  // Authentication (provide one)
  apiKey: "sand_personal_...", // API key authentication
  accessToken: "eyJhbG...", // JWT authentication

  // Configuration
  apiUrl: "https://api.sandstone.ai/graphql", // default
  timeout: 30_000, // request timeout in ms (default: 30s)


  // Retry behavior (queries only — mutations are never retried)
  retry: {
    maxRetries: 3, // default: 3
    initialDelayMs: 500, // default: 500ms
    maxDelayMs: 10_000, // default: 10s
  },

  // Middleware
  requestMiddleware: (ctx) => {
  // Inspect or modify headers before each request
    ctx.headers["x-custom"] = "value";
  },
  
  responseMiddleware: (ctx) => {
    // Inspect responses (read-only)
    console.log(`${ctx.operation} took ${ctx.duration}ms`);
  },

  // Token refresh callback
  onTokenExpired: async () => {
    // Called on 401 — refresh your token, then the request retries once
    const newToken = await refreshToken();
    client.setAccessToken(newToken);
  },
});