> For the complete documentation index, see [llms.txt](/llms.txt).

# wallet_watchAsset

Requests that the user track the specified token in MetaMask. Returns a boolean indicating if the token was successfully added. Once added, the token is indistinguishable from those added using legacy methods, such as a centralized registry. Introduced by [EIP-747](https://eips.ethereum.org/EIPS/eip-747).

### Parameters

`type`(string)required

The token type (`ERC20`, `ERC721`, or `ERC1155`). Support for ERC-721 and ERC-1155 tokens is experimental and currently only available on the extension (not on mobile). See [MIP-1](https://github.com/MetaMask/metamask-improvement-proposals/blob/main/MIPs/mip-1.md) and the [MIP proposal lifecycle](https://github.com/MetaMask/metamask-improvement-proposals/blob/main/PROCESS-GUIDE.md#proposal-lifecycle) for more information.

`options`(object)

An object containing information about the token.

options properties▼

### Returns

`true` if the token was added, `false` otherwise.

### Errors

| Code   | Description                                                                                                                                                            |
| ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| -32602 | Must specify address, symbol, and decimals.                                                                                                                            |
| -32602 | Invalid symbol: not a string.                                                                                                                                          |
| -32602 | Invalid symbol '${symbol}': longer than 11 characters.                                                                                                                 |
| -32602 | Invalid decimals '${decimals}': must be 0 <= 36.                                                                                                                       |
| -32602 | Invalid address '${address}'.                                                                                                                                          |
| -32602 | Asset type is required.                                                                                                                                                |
| -32602 | Both address and tokenId are required.                                                                                                                                 |
| -32602 | Invalid address.                                                                                                                                                       |
| -32000 | Suggested NFT is not owned by the selected account.                                                                                                                    |
| -32000 | Suggested NFT of type ${standard} does not match received type ${type}.                                                                                                |
| -32002 | Unable to verify ownership. Possibly because the standard is not supported or the user's currently selected network does not match the chain of the asset in question. |

Example request

```
await provider.request({
  method: 'wallet_watchAsset',
  params: [
    'ERC20',
    {
      address: '0xb60e8dd61c5d32be8058bb8eb970870f07233155',
      symbol: 'FOO',
      decimals: 18,
      image: 'https://foo.io/token-image.svg',
    },
  ],
})

```

Example response

```
{
  "id": 1,
  "jsonrpc": "2.0",
  "result": true
}

```