> ## Documentation Index
> Fetch the complete documentation index at: https://developers.particle.network/llms.txt
> Use this file to discover all available pages before exploring further.

# Universal Accounts SDK FAQ

> Frequently Asked Questions about the Universal Accounts SDK.

<AccordionGroup>
  <Accordion title="What is the Universal Accounts SDK?" icon="browser">
    The Universal Accounts SDK lets you integrate Particle Network's chain abstraction into your dApp. It provides your users with a unified address and balance across EVM chains and Solana.

    You can use this SDK to:

    * Allow users with assets on any chain to access your dApp.
    * Give your users a unified assets balance and identity across chains and ecosystems.
    * Execute transactions across chains without bridging or transferring assets.
  </Accordion>

  <Accordion title="Which platforms are supported by the SDK?" icon="desktop">
    The SDK is currently only available for Web.

    <Tip>
      Check out our [SDK Reference](/universal-accounts/ua-reference/desktop/web) for detailed platform-specific docs.
    </Tip>
  </Accordion>

  <Accordion title="What are Primary Assets, and how do they work?" icon="coins">
    Primary Assets are tokens with deep liquidity, used by the Universal Accounts SDK as sources for cross-chain transactions. These assets are used for gas, swaps, and liquidity routing across chains.

    <Info>
      Find a list of the supported Primary Assets in the [Supported Chains & Primary Assets](/universal-accounts/cha/chains#primary-assets) page.
    </Info>

    Users can hold Primary assets on any [supported chain](/universal-accounts/cha/chains). When a transaction (like a swap or transfer) is initiated, the SDK will:

    * Identify the most optimal Primary Asset from the user’s portfolio. For example, it may select USD on Polygon to allow a user to purchase a memecoin on Solana.
    * Route liquidity across all the chains the user holds this Primary Asset using Universal Liquidity.
    * Complete the transaction on the destination chain, even if the user holds **no assets on that chain.**
  </Accordion>

  <Accordion title="Do users need to deposit assets into their Universal Account?" icon="vault">
    Yes. Universal Accounts are ERC-4337 smart account implementations, which means users must deposit assets into them before they can be used.

    However, if a user already holds funds on another app leveraging Universal Accounts, like [UniversalX](https://universalx.app), those balances will be already available and usable within your dApp

    To enable swaps, transfers, or contract calls:

    * Users must hold **at least one [Primary Asset](/universal-accounts/cha/chains#primary-assets)** on their Universal Account.
    * Once deposited, the SDK can route liquidity across supported chains.
  </Accordion>

  <Accordion title="Do Universal Accounts have private keys?" icon="lock-open">
    No. Universal Accounts are ERC-4337 smart accounts—they don’t have private keys like traditional EOAs (Externally Owned Accounts).

    Instead, ownership and permissions are managed via a signer (such as a user's wallet or social login) that authorizes transactions.
  </Accordion>

  <Accordion title="What are the transaction fees?" icon="file-invoice-dollar">
    Particle Network applies fees to **buy** and **sell** transactions executed through **Universal Accounts**.

    Fee structures are not fixed and are defined **per project**, based on factors such as use case, volume, and integration requirements.

    For detailed pricing or to discuss a custom fee model, contact\
    [Particle Support](https://t.me/particle_developer_bot).
  </Accordion>

  <Accordion title="How to fix the 'Buffer is not defined' error in Vite" icon="bug">
    This error happens because Vite doesn't polyfill Node.js globals like `Buffer` in the browser. However, some SDK dependencies (like `ethers`) may expect it to be available.

    To fix this, follow these steps:

    ### 1. Install required packages

    ```bash theme={null}
    npm install buffer
    npm install --save-dev @esbuild-plugins/node-globals-polyfill @esbuild-plugins/node-modules-polyfill
    ```

    1. Update your `vite.config.ts`

    ```ts vite.config.ts theme={null}
    import { defineConfig } from 'vite'
    import react from '@vitejs/plugin-react'
    import { NodeGlobalsPolyfillPlugin } from '@esbuild-plugins/node-globals-polyfill'
    import { NodeModulesPolyfillPlugin } from '@esbuild-plugins/node-modules-polyfill'

    export default defineConfig({
      plugins: [react()],
      optimizeDeps: {
        esbuildOptions: {
          define: {
            global: 'globalThis'
          },
          plugins: [
            NodeGlobalsPolyfillPlugin({
              buffer: true
            }),
            NodeModulesPolyfillPlugin()
          ]
        }
      },
      resolve: {
        alias: {
          buffer: 'buffer'
        }
      }
    })
    ```
  </Accordion>

  <Accordion title="Could not find a declaration file for module '@particle-network/universal-account-sdk'." icon="file">
    You might get this error when using TypeScript. To fix it, you can add a declaration in `tsconfig.json`.

    Add `./node_modules/@particle-network/universal-account-sdk/dist/index.d.ts` to the `paths` property in `tsconfig.json`.

    ```json theme={null}
    {
      "paths": {
        "@/*": ["./*"],
        "@particle-network/universal-account-sdk": ["./node_modules/@particle-network/universal-account-sdk/dist/index.d.ts"]
      }
    }
    ```

    This will solve the declaration error.
  </Accordion>
</AccordionGroup>

<Note>
  **Still need help?** \ Reach out via our[
  Telegram](https://t.me/particle_developer_bot) **support channel** to get
  direct help from Particle’s Developer Relations team.
</Note>