<p>Updates the shard count of the specified stream to the specified number of shards. This API is only supported for the data streams with the provisioned capacity mode.</p> <note> <p>When invoking this API, it is recommended you use the <code>StreamARN</code> input parameter rather than the <code>StreamName</code> input parameter.</p> </note> <p>Updating the shard count is an asynchronous operation. Upon receiving the request, Kinesis Data Streams returns immediately and sets the status of the stream to <code>UPDATING</code>. After the update is complete, Kinesis Data Streams sets the status of the stream back to <code>ACTIVE</code>. Depending on the size of the stream, the scaling action could take a few minutes to complete. You can continue to read and write data to your stream while its status is <code>UPDATING</code>.</p> <p>To update the shard count, Kinesis Data Streams performs splits or merges on individual shards. This can cause short-lived shards to be created, in addition to the final shards. These short-lived shards count towards your total shard limit for your account in the Region.</p> <p>When using this operation, we recommend that you specify a target shard count that is a multiple of 25% (25%, 50%, 75%, 100%). You can specify any target value within your shard limit. However, if you specify a target that isn't a multiple of 25%, the scaling action might take longer to complete. </p> <p>This operation has the following default limits. By default, you cannot do the following:</p> <ul> <li> <p>Scale more than ten times per rolling 24-hour period per stream</p> </li> <li> <p>Scale up to more than double your current shard count for a stream</p> </li> <li> <p>Scale down below half your current shard count for a stream</p> </li> <li> <p>Scale up to more than 10000 shards in a stream</p> </li> <li> <p>Scale a stream with more than 10000 shards down unless the result is less than 10000 shards</p> </li> <li> <p>Scale up to more than the shard limit for your account</p> </li> </ul> <p>For the default limits for an Amazon Web Services account, see <a href="https://docs.aws.amazon.com/kinesis/latest/dev/service-sizes-and-limits.html">Streams Limits</a> in the <i>Amazon Kinesis Data Streams Developer Guide</i>. To request an increase in the call rate limit, the shard limit for this API, or your overall shard limit, use the <a href="https://console.aws.amazon.com/support/v1#/case/create?issueType=service-limit-increase&amp;limitType=service-code-kinesis">limits form</a>.</p>

{
  "success": true,
  "data": {
    "id": "abc123",
    "created_at": "2025-01-01T00:00:00Z"
  }
}

{
  "success": false,
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Invalid request parameters"
  }
}