> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter-d02e98a0-mintlify-5b6e02fd.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ChatStreamingResponseChunkData - Python SDK

> ChatStreamingResponseChunkData method reference

<Warning>
  The Python SDK and docs are currently in beta.
  Report issues on [GitHub](https://github.com/OpenRouterTeam/python-sdk/issues).
</Warning>

## Fields

| Field                | Type                                                                                                       | Required             | Description |
| -------------------- | ---------------------------------------------------------------------------------------------------------- | -------------------- | ----------- |
| `id`                 | *str*                                                                                                      | :heavy\_check\_mark: | N/A         |
| `choices`            | List\[[components.ChatStreamingChoice](/client-sdks/python/components/chatstreamingchoice)]                | :heavy\_check\_mark: | N/A         |
| `created`            | *float*                                                                                                    | :heavy\_check\_mark: | N/A         |
| `model`              | *str*                                                                                                      | :heavy\_check\_mark: | N/A         |
| `object`             | *Literal\["chat.completion.chunk"]*                                                                        | :heavy\_check\_mark: | N/A         |
| `system_fingerprint` | *OptionalNullable\[str]*                                                                                   | :heavy\_minus\_sign: | N/A         |
| `error`              | [Optional\[components.ChatStreamingResponseChunkError\]](../components/chatstreamingresponsechunkerror.md) | :heavy\_minus\_sign: | N/A         |
| `usage`              | [Optional\[components.ChatGenerationTokenUsage\]](../components/chatgenerationtokenusage.md)               | :heavy\_minus\_sign: | N/A         |