v4 follow-up: banners + v5 rewrites for low-level-infra and smart-contracts

content/tutorials/getting-started/alchemy-quickstart-guide.mdx

@@ -109,35 +109,32 @@ Ship smart wallets in minutes with the Account Kit SDK:
 
 Ship for web and mobile with React, React Native, or other JS frameworks.
 
-Check out the [Smart Wallets quickstart](/docs/wallets/react/quickstart) to get started.
+Check out the [Smart Wallets quickstart](/docs/wallets/quickstart) to get started.
 
 ### Send a gas-free smart wallet transaction
 
 ```ts
-// yarn add @account-kit/infra @account-kit/smart-contracts
-import {
-  alchemy,
-  createAlchemySmartAccountClient,
-  sepolia,
-} from "@account-kit/infra";
-import { createLightAccount } from "@account-kit/smart-contracts";
-import { LocalAccountSigner } from "@aa-sdk/core";
-import { generatePrivateKey } from "viem/accounts";
-
-const alchemyTransport = alchemy({
-  apiKey: "YOUR_API_KEY", // from Alchemy dashboard
+// yarn add @alchemy/wallet-apis viem
+import { createSmartWalletClient, alchemyWalletTransport } from "@alchemy/wallet-apis";
+import { arbitrumSepolia } from "viem/chains";
+import { privateKeyToAccount, generatePrivateKey } from "viem/accounts";
+import { zeroAddress } from "viem";
+
+export const client = createSmartWalletClient({
+  transport: alchemyWalletTransport({
+    apiKey: "YOUR_API_KEY", // from Alchemy dashboard
+  }),
+  chain: arbitrumSepolia,
+  signer: privateKeyToAccount(generatePrivateKey()),
+  paymaster: {
+    policyId: "YOUR_POLICY_ID", // create a gas policy in the dashboard
+  },
 });
 
-export const client = createAlchemySmartAccountClient({
-  transport: alchemyTransport,
-  policyId: "YOUR_POLICY_ID", // create a gas policy in the dashboard
-  chain: sepolia,
-  account: await createLightAccount({
-    chain: sepolia,
-    transport: alchemyTransport,
-    signer: LocalAccountSigner.privateKeyToAccountSigner(generatePrivateKey()),
-  }),
+const { id } = await client.sendCalls({
+  calls: [{ to: zeroAddress, value: BigInt(0) }],
 });
+const status = await client.waitForCallsStatus({ id });
 ```
 
 ***

content/wallets/pages/authentication/login-methods/bring-your-own-auth.mdx

@@ -4,6 +4,8 @@ description: Integrate your existing authentication system with Wallet APIs usin
 slug: wallets/authentication/login-methods/bring-your-own-auth
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 Integrate your existing authentication provider and add smart wallet functionality to your app without changing your users' login experience. Wallet APIs supports JWT-based and OIDC-compliant authentication providers.
 
 ## Prerequisites

content/wallets/pages/authentication/login-methods/email-magic-link.mdx

@@ -4,6 +4,8 @@ description: How to implement Email Magic Link authentication across different f
 slug: wallets/authentication/login-methods/email-magic-link
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 Email magic link authentication is a two-step process:
 
 1. The user enters their email address and requests a magic link

content/wallets/pages/authentication/login-methods/email-otp.mdx

@@ -4,6 +4,8 @@ description: How to implement Email OTP authentication across different framewor
 slug: wallets/authentication/login-methods/email-otp
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 Email OTP (One-Time Password) authentication is a two-step process:
 
 1. The user enters their email address and requests a verification code

content/wallets/pages/authentication/login-methods/passkey-signup.mdx

@@ -4,6 +4,8 @@ description: How to implement Passkey Signup authentication across different fra
 slug: wallets/authentication/login-methods/passkey-signup
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 Passkeys provide a secure, passwordless authentication method that can be used to create wallets for your users without going through email verification flows. You can implement passkey signup with or without an associated email address.
 
 <Markdown src="../../../shared/passkey-email-warning.mdx" />

content/wallets/pages/authentication/login-methods/sms-login.mdx

@@ -4,6 +4,8 @@ description: How to authenticate users with phone number and SMS OTP code
 slug: wallets/authentication/login-methods/sms-login
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 <Info>
   SMS auth is currently in closed alpha. If you'd like early access please reach
   out to [wallets@alchemy.com](mailto:wallets@alchemy.com).

content/wallets/pages/authentication/login-methods/social-login.mdx

@@ -4,6 +4,8 @@ description: How to implement Social Login authentication across different frame
 slug: wallets/authentication/login-methods/social-login
 ---
 
+<Markdown src="../../../shared/v4-signer-banner.mdx" />
+
 Social login authentication allows users to authenticate using OAuth providers like Google, Facebook, or custom providers through Auth0. There are two authentication flows available:
 
 1. **Redirect flow**: Redirects the user to the provider's login page and back to your application

content/wallets/pages/bundler-api/bundler-sponsored-operations.mdx

@@ -67,77 +67,68 @@ For more details, see the [Compute Unit Costs documentation](/docs/reference/com
 To enable bundler sponsorship, you need to:
 
 1. **Create a Bundler Sponsored Operations policy** in your dashboard with the required Max Spend Per UO configuration
-2. **Include the policy ID** in your requests via the `x-alchemy-policy-id` header
-3. **Set gas fees to zero** in your user operation overrides
+2. **Include the policy ID** in your requests via the `x-alchemy-policy-id` header on the bundler transport
+3. **Zero out `maxFeePerGas`, `maxPriorityFeePerGas`, and `preVerificationGas`** on the user operation
 
 ### Example implementation
 
-Here's a complete example using Wallet APIs to send a sponsored user operation:
+Below is the low-level (viem) pattern. The policy ID rides on the bundler transport's `fetchOptions.headers`; the bundler fills in the actual gas values server-side when it sees the zeroed fields.
 
-```typescript
-import { LocalAccountSigner } from "@aa-sdk/core";
-import { alchemy, worldChain } from "@account-kit/infra";
-import { createModularAccountV2Client } from "@account-kit/smart-contracts";
+```ts
+import { createClient, type Hex } from "viem";
+import { createBundlerClient } from "viem/account-abstraction";
+import { privateKeyToAccount } from "viem/accounts";
+import { worldchain } from "viem/chains";
+import { alchemyTransport } from "@alchemy/common";
+import { toModularAccountV2 } from "@alchemy/smart-accounts";
+import { estimateFeesPerGas } from "@alchemy/aa-infra";
 
-const RPC_URL = process.env.RPC_URL!;
+const ALCHEMY_API_KEY = process.env.ALCHEMY_API_KEY!;
 const POLICY_ID = process.env.POLICY_ID!;
-const PRIVATE_KEY = process.env.PRIVATE_KEY!;
-
-(async () => {
-  try {
-    const chain = worldChain;
-
-    // Configure transport with bundler sponsorship header
-    const transport = alchemy({
-      rpcUrl: RPC_URL,
-      fetchOptions: {
-        headers: {
-          "x-alchemy-policy-id": POLICY_ID
-        }
-      }
-    });
-
-    const signer = LocalAccountSigner.privateKeyToAccountSigner(
-      PRIVATE_KEY as `0x${string}`
-    );
-
-    const client = await createModularAccountV2Client({
-      chain,
-      transport,
-      signer,
-    });
-
-    // Send user operation with bundler sponsorship
-    const uo = await client.sendUserOperation({
-      overrides: {
-        maxFeePerGas: "0x0",
-        maxPriorityFeePerGas: "0x0",
-      },
-      uo: {
-        target: "0x0000000000000000000000000000000000000000",
-        data: "0x",
-      },
-    });
-
-    const txHash = await client.waitForUserOperationTransaction({
-      hash: uo.hash,
-    });
-
-    console.log("Tx Hash: ", txHash);
-
-  } catch (err) {
-    console.error("Error:", err);
-  }
-})();
+const PRIVATE_KEY = process.env.PRIVATE_KEY! as Hex;
+
+// The policy ID rides on the transport's fetch options.
+const transport = alchemyTransport({
+  apiKey: ALCHEMY_API_KEY,
+  fetchOptions: {
+    headers: { "x-alchemy-policy-id": POLICY_ID },
+  },
+});
+
+const rpcClient = createClient({ chain: worldchain, transport });
+
+const account = await toModularAccountV2({
+  client: rpcClient,
+  owner: privateKeyToAccount(PRIVATE_KEY),
+});
+
+const bundlerClient = createBundlerClient({
+  account,
+  client: rpcClient,
+  chain: worldchain,
+  transport,
+  userOperation: { estimateFeesPerGas },
+});
+
+// Zero ALL three gas fields — the bundler fills them in.
+const hash = await bundlerClient.sendUserOperation({
+  calls: [{ to: "0x000000000000000000000000000000000000dEaD", data: "0x" }],
+  maxFeePerGas: 0n,
+  maxPriorityFeePerGas: 0n,
+  preVerificationGas: 0n,
+});
+
+const receipt = await bundlerClient.waitForUserOperationReceipt({ hash });
+console.log("Tx:", receipt.receipt.transactionHash);
 ```
 
 ### Key configuration points
 
 1. **Policy Type**: Ensure you've created a policy of type "Bundler Sponsored Operations" with Max Spend Per UO configured.
 
-2. **Transport Configuration**: The `x-alchemy-policy-id` header must be included in the transport configuration's `fetchOptions.headers`.
+2. **Transport Configuration**: The `x-alchemy-policy-id` header must be included on the **bundler** transport via `fetchOptions.headers`. No `createPaymasterClient` needed — BSO does not use a paymaster contract.
 
-3. **Gas Fee Overrides**: Set both `maxFeePerGas` and `maxPriorityFeePerGas` to `"0x0"` to indicate that the bundler should sponsor all gas costs.
+3. **Gas Fee Overrides**: Set `maxFeePerGas`, `maxPriorityFeePerGas`, **and** `preVerificationGas` to `0n` on the user operation. All three must be zero — the bundler treats that as the signal to cover gas under the BSO policy.
 
 ## Requirements
 

content/wallets/pages/concepts/middleware.mdx

@@ -4,6 +4,8 @@ description: What is Middleware?
 slug: wallets/concepts/middleware
 ---
 
+<Markdown src="../../shared/v4-concept-banner.mdx" />
+
 The [Smart Account Client](/docs/wallets/concepts/smart-account-client) is extended with a series of middleware. When building transactions for signing and sending, the flow can be involved.
 Sending a transaction requires getting the latest nonce for an account, checking if the account is deployed to set the `initCode` or `factory` and `factoryData`, estimating fees, estimating gas, and then signing the transaction.
 If you want to sponsor gas, you need to generate some `dummyPaymasterAndData` to use during gas estimation, and after estimating gas you can request gas sponsorship.

content/wallets/pages/core/overview.mdx

@@ -4,6 +4,8 @@ description: How to use Wallet APIs with other JavaScript frameworks
 slug: wallets/core/overview
 ---
 
+<Markdown src="../../shared/v4-code-banner.mdx" />
+
 There are no current plans to support other JavaScript front-end frameworks such as Vue, Angular, or Svelte. However, there are a number of different ways to integrate Wallet APIs within your application if you're using one of these JavaScript frameworks.
 
 <Tip>

content/wallets/pages/core/quickstart.mdx

@@ -4,6 +4,9 @@ description: Learn how to get started with the Wallet APIs Core package
 slug: wallets/core/quickstart
 ---
 
+{/* No inbound links from other /content pages as of 2026-05-22 — candidate for retirement rather than v5 rewrite. */}
+<Markdown src="../../shared/v4-code-banner.mdx" />
+
 If you're not using React, but still want a number of the abstractions that make the React package straightforward to use, leverage the `@account-kit/core` package directly.
 
 In this guide, learn how to use this package to send a transaction, while using the reactive utilities exported by this package.

content/wallets/pages/infra/quickstart.mdx

@@ -4,6 +4,8 @@ description: Get started with Wallet APIs infrastructure
 slug: wallets/infra/quickstart
 ---
 
+<Markdown src="../../shared/v4-code-banner.mdx" />
+
 Wallet APIs is composed of some lower-level libraries if you're looking for further customization of your stack or want more control over how you build your application.
 One of these libraries is `@account-kit/infra` which allows you to interact with our infrastructure directly, while bringing your own smart contracts or signer.
 In this guide, learn how to get started with `@account-kit/infra` and send a transaction. For smart contracts, the guide leverages `@account-kit/smart-contracts` to use `LightAccount`,

content/wallets/pages/low-level-infra/bundler/overview.mdx

@@ -4,9 +4,10 @@ description: Raw EIP-4337 Bundler APIs for advanced developers
 slug: wallets/transactions/low-level-infra/bundler/overview
 ---
 
-The Bundler is a key component in the ERC-4337 stack, responsible for collecting, validating, and bundling UserOperations (UserOps) into transactions that are submitted to the EntryPoint contract on the blockchain. The Bundler APIs provide direct access to high-performance, scalable infrastructure (powered by Rundler), enabling developers to interact with a production-grade ERC-4337 bundler for reliable onchain submission of UserOps.
-These APIs are part of the `@account-kit/infra` library, allowing advanced customization when building smart wallet applications. They follow the standard ERC-4337 JSON-RPC endpoints and support versions v0.6, v0.7, and v0.8 of the protocol, with optimizations for gas estimation, validation, and error handling to ensure UserOps land efficiently while protecting against attacks.
+The Bundler is a key component in the ERC-4337 stack, responsible for collecting, validating, and bundling UserOperations (UserOps) into transactions submitted to the EntryPoint contract on the blockchain. The Bundler APIs provide direct access to Alchemy's high-performance, scalable infrastructure (powered by Rundler), letting developers interact with a production-grade ERC-4337 bundler for reliable onchain submission of UserOps.
 
-For full control, bring your own smart contracts or authentication providers while leveraging the bundler for scalability. If you prefer a higher-level abstraction, use the Wallet APIs or aa-sdk instead.
+These endpoints follow the standard ERC-4337 JSON-RPC interface and support v0.6, v0.7, and v0.8 of the protocol, with optimizations for gas estimation, validation, and error handling.
+
+If you want SDK-level access, use viem's [`createBundlerClient`](https://viem.sh/account-abstraction/clients/bundler) with `alchemyTransport({ apiKey })` from [`@alchemy/common`](/docs/wallets/reference/common) as the transport, and pass [`@alchemy/aa-infra`](/docs/wallets/reference/aa-infra)'s `estimateFeesPerGas` helper as the fee estimator. For a higher-level abstraction, use [`@alchemy/wallet-apis`](/docs/wallets/quickstart) instead.
 
 <Markdown src="../../../shared/infra/api-endpoints/bundler.mdx" />