Add app accounts sdk docs

apps/base-docs/docs/pages/identity/smart-wallet/features/app-accounts.mdx

@@ -0,0 +1,9 @@
+# App Accounts
+
+App Accounts enable developers to create and manage app-specific accounts for their applications. These accounts are linked to the user's Smart Wallet and can be utilized to sign transactions specifically for the app. This integration grants developers full control over the user experience, ensuring a seamless and cohesive interaction within the app.
+
+## Technical Details
+
+- Smart Wallet Ownership: The user's Smart Wallet acts as an owner of the app account, allowing it to manage and control the app-specific account.
+- Key Agnostic: App Accounts are designed to be key agnostic. They leverage our Linked Accounts technology, which supports various key types including in-browser CryptoKeys, Passkeys, and server signer products.
+- App Accounts can be used to sign transactions, messages, and EIP-712 typed data.

apps/base-docs/docs/pages/identity/smart-wallet/guides/app-accounts/overview.mdx

@@ -0,0 +1,86 @@
+# App Accounts
+
+App Accounts enable developers to create and manage app-specific accounts for their applications. These accounts are linked to the user's Smart Wallet and can be utilized to sign transactions specifically for the app. This integration grants developers full control over the user experience, ensuring a seamless and cohesive interaction within the app.
+
+App Accounts can be interacted with via the Coinbase Wallet SDK.
+
+## How it works
+
+1. An application can create an app account for a user by using the `wallet_addAccount` RPC method. See [EIP-XXXX](https://eips.ethereum.org/EIPS/eip-XXXX) for more details.
+2. The application can either create the account themselves or provide a signer for the Smart Wallet to create the account.
+3. Once the account is created, the application can use the account to sign transactions, messages, and EIP-712 typed data.
+
+## Example (creating a new app account)
+
+```typescript
+import { createCoinbaseWalletSDK } from '@coinbase/coinbase-sdk';
+import { privateKeyToAccount } from 'viem/accounts';
+
+const sdk = new createCoinbaseWalletSDK({
+  appName: 'My App',
+  appLogoUrl: 'https://myapp.com/logo.png',
+  appChainIds: [84532],
+  subAccount: {
+    getSigner: async () => {
+      return privateKeyToAccount('0x...');
+    },
+  },
+});
+
+const provider = sdk.getProvider();
+
+const response = await provider.request({
+  method: 'wallet_addAccount',
+  params: [
+    {
+      version: 1,
+      account: {
+        signers: [
+          {
+            type: 'key',
+            data: {
+              publicKey: '0x...',
+              type: 'secp256k1',
+            },
+          },
+          {
+            type: 'account',
+            data: {
+              address: '0x...',
+            },
+          },
+        ],
+      },
+    },
+  ],
+});
+```
+
+## Example (using an existing app account)
+
+```typescript
+const sdk = new createCoinbaseWalletSDK({
+  appName: 'My App',
+  appLogoUrl: 'https://myapp.com/logo.png',
+  appChainIds: [84532],
+  subAccount: {
+    getSigner: async () => {
+      return privateKeyToAccount('0x...');
+    },
+  },
+});
+
+const provider = sdk.getProvider();
+
+const response = await provider.request({
+  method: 'wallet_addAccount',
+  params: [
+    {
+      version: 1,
+      account: {
+        address: '0x...',
+      },
+    },
+  ],
+});
+```

apps/base-docs/docs/pages/identity/smart-wallet/sdk/snippets/sdk-paramaters.mdx

@@ -1,20 +1,23 @@
-import PreferenceParameters from './preference-parameters.mdx'
+import PreferenceParameters from './preference-parameters.mdx';
 
 ## Parameters
 
 ### appName (optional)
+
 - Type: `string`
 
 The app name. This will be displayed to users on connection, transacting, and signing requests.
 
 ### appChainIds (optional)
+
 - Type: `number[]`
 
 Array of chain IDs your app supports. Default value is `[1]`.
 
 [What networks are supported?](/identity/smart-wallet/FAQ#what-networks-are-supported)
 
 ### appLogoUrl (optional)
+
 - Type: `string`
 
 App logo image URL. Favicon is used if unspecified.
@@ -23,4 +26,16 @@ App logo image URL. Favicon is used if unspecified.
 Local paths are not supported for `appLogoUrl` as the logo is presented on another window as popup. Please provide a non-local URL.
 :::
 
+### subAccount (optional)
+
+- Type: `object`
+
+Subaccount configuration.
+
+#### getSigner
+
+- Type: `function`
+
+Function that returns a signer for the subaccount. This function should resolve to a Viem LocalAccount or a Viem WebAuthnAccount
+
 <PreferenceParameters />