> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter-d02e98a0-mintlify-7021d5f4.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# FunctionCallArgsDeltaEvent - Go SDK

> FunctionCallArgsDeltaEvent type definition

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

Event emitted when function call arguments are being streamed

## Fields

| Field            | Type                                                                                                             | Required             | Description |
| ---------------- | ---------------------------------------------------------------------------------------------------------------- | -------------------- | ----------- |
| `Delta`          | `string`                                                                                                         | :heavy\_check\_mark: | N/A         |
| `ItemID`         | `string`                                                                                                         | :heavy\_check\_mark: | N/A         |
| `OutputIndex`    | `int64`                                                                                                          | :heavy\_check\_mark: | N/A         |
| `SequenceNumber` | `int64`                                                                                                          | :heavy\_check\_mark: | N/A         |
| `Type`           | [components.FunctionCallArgsDeltaEventType](/client-sdks/go/api-reference/models/functioncallargsdeltaeventtype) | :heavy\_check\_mark: | N/A         |