To check for the number of documents in a [data stream]({{site.url}}{{site.baseurl}}/opensearch/data-streams/), replace the index name with the data stream name.
Alternatively, you could use the [cat indexes]({{site.url}}{{site.baseurl}}/api-reference/cat/cat-indices/) and [cat count]({{site.url}}{{site.baseurl}}/api-reference/cat/cat-count/) APIs to see the number of documents per index or data stream.
`allow_no_indices` | Boolean | If false, the request returns an error if any wildcard expression or index alias targets any closed or missing indexes. Default is false.
`expand_wildcards` | String | Specifies the type of index that wildcard expressions can match. Supports comma-separated values. Valid values are `all` (match any index), `open` (match open, non-hidden indexes), `closed` (match closed, non-hidden indexes), `hidden` (match hidden indexes), and `none` (deny wildcard expressions). Default is `open`.
`ignore_unavailable` | Boolean | Specifies whether to include missing or closed indexes in the response. Default is false.
`lenient` | Boolean | Specifies whether OpenSearch should accept requests if queries have format errors (for example, querying a text field for an integer). Default is false.
`min_score` | Float | Include only documents with a minimum `_score` value in the result.
`routing` | String | Value used to route the operation to a specific shard.
`preference` | String | Specifies which shard or node OpenSearch should perform the count operation on.
`terminate_after` | Integer | The maximum number of documents OpenSearch should process before terminating the request.