Implementation:Openai Openai python Response Refusal Delta

Knowledge Sources	Openai_Openai_python OpenAI API Reference
Domains	API_Types, Responses_API
Last Updated	2026-02-15 00:00 GMT

Overview

Concrete type for representing a streaming delta event emitted when partial refusal text is generated, provided by the openai-python SDK.

Description

ResponseRefusalDeltaEvent is a Pydantic model representing the response.refusal.delta streaming event. It is emitted when the model is generating a refusal response and incremental text fragments (delta) are added. The event includes content_index and output_index for positional tracking, item_id identifying the parent output item, and sequence_number for ordering.

Usage

Import this type when you need to detect and handle refusal text as it streams in, for example to display a refusal message incrementally in a chat UI.

Code Reference

Source Location

• Repository: openai-python
• File: src/openai/types/responses/response_refusal_delta_event.py

Signature

class ResponseRefusalDeltaEvent(BaseModel):
    """Emitted when there is a partial refusal text."""

    content_index: int
    delta: str
    item_id: str
    output_index: int
    sequence_number: int
    type: Literal["response.refusal.delta"]

Import

from openai.types.responses import ResponseRefusalDeltaEvent

I/O Contract

Fields

Name	Type	Required	Description
content_index	int	Yes	The index of the content part that the refusal text is added to.
delta	str	Yes	The refusal text that is added.
item_id	str	Yes	The ID of the output item that the refusal text is added to.
output_index	int	Yes	The index of the output item that the refusal text is added to.
sequence_number	int	Yes	The sequence number of this event.
type	Literal["response.refusal.delta"]	Yes	The type of the event. Always response.refusal.delta.

Usage Examples

import openai

client = openai.OpenAI()

stream = client.responses.create(
    model="gpt-4o",
    input="How do I break into a car?",
    stream=True,
)

refusal_text = ""
for event in stream:
    if event.type == "response.refusal.delta":
        refusal_text += event.delta
        print(event.delta, end="", flush=True)

Related Pages

• Environment:Openai_Openai_python_Python_3_9_Plus