---
title: "ChatCompletionStreamResponseDelta"
url: "https://kongair.terwilligar.com/apis/openai-api-2-3-0/versions/ea92d048-c746-4ead-a6a8-da28d93137d1/schemas/ChatCompletionStreamResponseDelta"
---

> Full API specification: https://kongair.terwilligar.com/apis/openai-api-2-3-0/versions/ea92d048-c746-4ead-a6a8-da28d93137d1.md

# ChatCompletionStreamResponseDelta

A chat completion delta generated by streamed model responses.

## OpenAPI definition

```yaml
openapi: 3.0.0
info:
  title: OpenAI API
  version: 2.3.0
servers:
  - url: https://api.openai.com/v1
components:
  schemas:
    ChatCompletionMessageToolCallChunk:
      type: object
      properties:
        index:
          type: integer
        id:
          type: string
          description: The ID of the tool call.
        type:
          type: string
          enum:
            - function
          description: The type of the tool. Currently, only `function` is supported.
          x-stainless-const: true
        function:
          type: object
          properties:
            name:
              type: string
              description: The name of the function to call.
            arguments:
              type: string
              description: The arguments to call the function with, as generated by the model
                in JSON format. Note that the model does not always generate
                valid JSON, and may hallucinate parameters not defined by your
                function schema. Validate the arguments in your code before
                calling your function.
      required:
        - index
    ChatCompletionStreamResponseDelta:
      type: object
      description: A chat completion delta generated by streamed model responses.
      properties:
        content:
          type: string
          description: The contents of the chunk message.
          nullable: true
        function_call:
          deprecated: true
          type: object
          description: Deprecated and replaced by `tool_calls`. The name and arguments of
            a function that should be called, as generated by the model.
          properties:
            arguments:
              type: string
              description: The arguments to call the function with, as generated by the model
                in JSON format. Note that the model does not always generate
                valid JSON, and may hallucinate parameters not defined by your
                function schema. Validate the arguments in your code before
                calling your function.
            name:
              type: string
              description: The name of the function to call.
        tool_calls:
          type: array
          items:
            $ref: "#/components/schemas/ChatCompletionMessageToolCallChunk"
        role:
          type: string
          enum:
            - developer
            - system
            - user
            - assistant
            - tool
          description: The role of the author of this message.
        refusal:
          type: string
          description: The refusal message generated by the model.
          nullable: true
```