> For the complete documentation index, see [llms.txt](https://docs.startrail.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.startrail.io/startrail-sdk-js/startrail-api-methods/updatemetadata.md).

# Update Metadata

To know the methods calling to Startrail API from Startrail-Sdk-Js

## `updateMetadata()`

Update the metadata in the SRR.

{% hint style="info" %}
**ERC2981 royalty.** For a digital artwork issued with a royalty receiver, Startrail keeps the on-chain royalty basis points in line with `contractTerms.royaltyRate`. When an update changes the rate, or makes the SRR ineligible for a royalty (for example `isDigital` becomes `false`), Startrail sends a separate administrator transaction once the metadata update is confirmed on chain. The new value is visible through [`checkERC2981Royalty()`](/startrail-sdk-js/startrail-api-methods/checkerc2981royalty.md) after that transaction is mined, usually within a few minutes. A `royaltyRate` with more than two decimal places is rejected, as it is at issuance.
{% endhint %}

## Method parameters

| Variable                      | Type     | Description                                                                                                           |
| ----------------------------- | -------- | --------------------------------------------------------------------------------------------------------------------- |
| `startrailLUWContractAddress` | `string` | The address of LicensedUserWallet(LUW) contract.                                                                      |
| `contractAddress`             | `string` | The address of collection contract. Sets it when you want to associate collection contract address with the SRR.      |
| `tokenId`                     | `string` | Startrail Registry Record Token ID                                                                                    |
| `metadata`                    | `object` | Refer to the [Startrail Registry (SRR) data schema](/metadata-schema/startrail-registry-srr.md) for all possible data |

### Parameters Example

```
const res = await sdk.approveSRRByCommitment(
  {  
    startrailLUWContractAddress: '0x113c6880fc4a2664E125973BC0Dfd37d62Ec7c3f',
    tokenId: '212786904920',
    metadata: {
      "$schema": "https://api.startrail.io/api/v1/schema/registry-record-metadata.v2.0.schema.json",
      "$schemaIntegrity": "sha256-f63238ce3b8c4f8a99fb453d716d5451f75508c2e403a58af0412014187e7a61",
      "startbahnCertICTagUIDs": [
        "1234567890abcdef"
      ],
      "title": {
        "en": "A title",
        "ja": "タイトル",
        "zh": "一个标题"
      },
      "size": {
        "width": 200,
        "height": 400,
        "depth": 12.4,
        "unit": "pixel",
        "flexibleDescription": {
          "en": "flexibleDescription comes here",
          "ja": "自由だーーー"
        }
      },
      "medium": {
        "en": "Oil on canvas",
        "ja": "キャンバスに油彩",
        "zh": "布面油画"
      },
      "edition": {
        "uniqueness": "unique work",
        "proofType": "ED",
        "number": 1,
        "totalNumber": 3,
        "note": {
          "en": "some extra notes in 1 or more languages"
        }
      },
      "contractTerms": {
        "royaltyRate": 15.7,
        "fileURL": "https://startrail.io/whitepaper/startrail_wp_en_v1.1.pdf"
      },
      "note": {
        "en": "note",
        "zh": "注意"
      },
      "thumbnailURL": "https://storage.googleapis.com/opensea-prod.appspot.com/puffs/3.png",
      "yearOfCreation": {
        "en": "around 2010-2020",
        "ja": "2010年から2020年頃"
      },
      "isDigital": true,
      "digitalDataHash": "sha256-247e4b904322a1dd0b148cd77e8627ec7d391251380880ab4621726ecb945ef5",
      "digitalComponents": [
        {
          "hash": "sha256-247e4b904322a1dd0b148cd77e8627ec7d391251380880ab4621726ecb945ef5",
          "category": "artwork"
        }
      ],
      "attachmentFiles": [
        {
          "hash": "sha256-247e4b904322a1dd0b148cd77e8627ec7d391251380880ab4621726ecb945ef5",
          "category": "artwork"
        }
      ],
      "name": "some nft name",
      "description": "some nft description",
      "image": "https://storage.googleapis.com/opensea-prod.appspot.com/puffs/3.png",
      "external_url": "https://openseacreatures.io/3"
    }
  },
)

```

## Returns

`Promise` will be returned which resolves with a `Response` object upon a successful confirmation. `false` will be returned when user flow is cancelled in such a case that a user closes the popup modal.

If the confirmation fails, the `Promise` will resolve with an {error} object that describes the failure.

`Promise<Response | false>`

{% hint style="warning" %}
The use of "txReceiptId" will soon be deprecated and removed.
{% endhint %}

### Response

| Variable      | Type        | Description                                             |
| ------------- | ----------- | ------------------------------------------------------- |
| `txReceiptId` | `string`    | ID to identify transaction details in Startrail-API DB. |
| `tx`          | `TxDetails` | Transaction details                                     |

### TxDetails

| Variable          | Type     | Description                                              |
| ----------------- | -------- | -------------------------------------------------------- |
| `contractAddress` | `string` | The address of collection contract associated to the SRR |
| `metadataCID`     | `string` | A calculated metadataCID                                 |
| `tokenId`         | `string` | A calculated tokenId                                     |

### Error

Custom `Error` objects. Refer to the [Error Catalogue](/startrail-sdk-js/errors.md) for possible data.

### Response Example

```
{
  "txReceiptId": 0,
  "tx": {
      "contractAddress": "0x87Ef5da2c87e047E7F005Efb8b68a93Dc94D161c",
      "tokenId": "209850285627",
      "metadataCID": "bafkreibjdtcklpe5wjgh6qp2dqygaydm3d4xttfhaphgian73bpprkr7xu"
  }
}
```


---

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