# Get Object Metadata Changes

Use the sObject Describe resource and the `If-Modified-Since` HTTP header to determine if object metadata has changed.

You can include the `If-Modified-Since` header with a date in `EEE, dd MMM yyyy HH:mm:ss z` format when you use the [sObject Describe](/docs/platform/api-rest/guide/resources-sobject-describe.md) resource. If you do, response metadata will only be returned if the object metadata has changed since the provided date. If the metadata has not been modified since the provided date, a `304 Not Modified` status code is returned, with no response body.

The following example assumes that no changes, such as new custom fields, have been made to the Merchandise\_\_c object after July 3rd, 2013.

## Example sObject Describe request

```nolang
curl https://MyDomainName.my.salesforce.com/services/data/v68.0/sobjects/Merchandise__c/describe -H "Authorization: Bearer token" -H "If-Modified-Since: Wed, 3 Jul 2013 19:43:31 GMT"
```

## Example response body

No response body returned

## Example response status code

```nolang
HTTP/1.1 304 Not Modified
Date: Fri, 12 Jul 2013 05:03:24 GMT
```

If there were changes to Merchandise\_\_c made after July 3rd, 2013, the response body would contain the metadata for Merchandise\_\_c. See [Get Field and Other Metadata for an Object](/docs/platform/api-rest/guide/dome-sobject-describe.md) for an example.