diff --git a/package.json b/package.json
index 17c9ec3..7db942b 100644
--- a/package.json
+++ b/package.json
@@ -71,6 +71,7 @@
     "format:check": "prettier --check .",
     "lint": "npm run typecheck && npm run format:check && eslint .",
     "lint:fix": "prettier --write . && eslint . --fix",
+    "test": "tsx --test src/auth.test.ts",
     "test:client": "tsx test-client.ts",
     "typecheck": "tsc --noEmit"
   },
diff --git a/src/auth.test.ts b/src/auth.test.ts
new file mode 100644
index 0000000..b8417ea
--- /dev/null
+++ b/src/auth.test.ts
@@ -0,0 +1,41 @@
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import { Hono } from "hono";
+import { createProtectedRoute } from "./auth";
+import type { AppContext, Env } from "./env";
+
+test("protected routes return an MPP payment challenge", async () => {
+  const app = new Hono<AppContext>();
+  app.use(
+    "/paid",
+    createProtectedRoute({
+      amount: "0.01",
+      description: "Test payment",
+      pattern: "/paid",
+    }),
+  );
+  app.get("/paid", (c) => c.text("paid"));
+
+  const env: Env = {
+    JWT_SECRET: "test-jwt-secret-000000000000000000000000000000000000",
+    MPP_SECRET_KEY: "test-mpp-secret-000000000000000000000000000000000000",
+    PAYMENT_CURRENCY: "0x20c0000000000000000000000000000000000000",
+    PAY_TO: "0x000000000000000000000000000000000000dEaD",
+    PROTECTED_PATTERNS: [
+      {
+        amount: "0.01",
+        description: "Access to premium content for 1 hour",
+        pattern: "/premium/*",
+      },
+    ],
+    TEMPO_TESTNET: true,
+  };
+
+  const response = await app.request("http://localhost/paid", undefined, env);
+
+  assert.equal(response.status, 402);
+  assert.match(
+    response.headers.get("www-authenticate") ?? "",
+    /intent="charge"/,
+  );
+});
diff --git a/src/auth.ts b/src/auth.ts
index 9696a25..025af2b 100644
--- a/src/auth.ts
+++ b/src/auth.ts
@@ -82,7 +82,7 @@ export function createProtectedRoute(config: ProtectedRouteConfig) {
   return async (c: Context<AppContext>, next: Next) => {
     const mppx = Mppx.create({
       methods: [
-        tempo({
+        tempo.charge({
           currency: c.env.PAYMENT_CURRENCY,
           recipient: c.env.PAY_TO,
           testnet: c.env.TEMPO_TESTNET,