The OAuth of the agent economy.

import { signInWithTessera } from "@tessera/sdk";
import { useWalletClient } from "wagmi";

function SignInButton() {
  const { data: walletClient } = useWalletClient();

  async function handleSignIn() {
    if (!walletClient) return;
    const session = await signInWithTessera(walletClient, {
      statement: "Sign in to MyAgentApp to verify your Tessera identity.",
    });
    // session = {
    //   address:    "0x...",
    //   chainId:    8453,
    //   message:    "tesseracredit.com wants you to sign in...",
    //   signature:  "0x...",
    //   issuedAt:   "2026-05-21T...",
    //   expiresAt:  "2026-05-21T...",
    //   profile:    { ecosystem, score?, tier?, creditLineEstimate? }
    // }

    // Send to your backend or persist however you store sessions.
    await fetch("/my-app/sessions", {
      method: "POST",
      body: JSON.stringify(session),
    });
  }

  return <button onClick={handleSignIn}>Sign in with Tessera</button>;
}

// Option A — verify with the SDK (recommended)
import { verifyTesseraSession } from "@tessera/sdk";

export async function POST(req: Request) {
  const session = await req.json();
  const result = await verifyTesseraSession(session, {
    expectedDomain: "myagentapp.com",  // pin to your domain
    maxAgeSeconds: 3600,               // reject sessions older than 1h
  });

  if (!result.valid) {
    return new Response(`unauthorized: ${result.reason}`, { status: 401 });
  }

  // result.address is the verified wallet — trust it.
  await mySession.create({ user: result.address });
  return new Response("ok");
}

// Option B — POST to the Tessera hosted endpoint
const res = await fetch("https://www.tesseracredit.com/api/auth/verify", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    session,
    options: { expectedDomain: "myagentapp.com", maxAgeSeconds: 3600 },
  }),
});
const { valid, address, reason } = await res.json();
if (!valid) throw new Error(`unauthorized: ${reason}`);