docs: Privy v3 integration example needed — OnboardPrivyOptions.privy.resolve API is underdocumented

[nagavaishak]

Summary

The OnboardStrategy.Privy integration is missing a practical end-to-end example. The OnboardPrivyOptions.privy.resolve function requires returning { walletId, publicKey, rawSign? }, but there's no documentation on how to implement rawSign with Privy v3's server auth SDK (@privy-io/server-auth).

Problem

When building with Privy v3 (@privy-io/react-auth v3.x), the client-side wallet API differs significantly from earlier versions. Specifically:

1. How to obtain walletId from a Privy embedded Starknet wallet using v3 client SDK
2. How to implement rawSign(walletId, messageHash) using PrivyClient.walletApi.rpc with caip2: "starknet:SN_SEPOLIA"
3. How to bridge the Privy auth token from client → server for signing

Suggested Fix

Add a complete Next.js App Router example showing:

// pages/api/sign.ts (server-side Privy signing proxy)
import { PrivyClient } from "@privy-io/server-auth";

const privy = new PrivyClient(appId, appSecret);

// rawSign implementation for StarkZap OnboardStrategy.Privy
async function rawSign(walletId: string, hash: string): Promise<string> {
  const { data } = await (privy.walletApi.rpc as any)({
    walletId,
    method: "starknet_signMessage",
    params: { message: hash },
    caip2: "starknet:SN_SEPOLIA",
  });
  return data.signature;
}

Environment

• starkzap v1.0.0
• @privy-io/react-auth v3.15.0
• @privy-io/server-auth v1.32.5
• Next.js 16 App Router
• Starknet Sepolia

Reference

Built this integration in StarkFolio (hackathon project): https://github.com/nagavaishak/StarkFolio

[0xLucqs]

Hello, which part is unclear ? the part on the server or on the client ?