Implementation:Openai Openai python Response Content Part Done Event

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

Overview

Concrete streaming event type emitted when a content part within a response output item is done, provided by the openai-python SDK.

Description

ResponseContentPartDoneEvent is a Pydantic model representing a streaming event emitted when a content part finishes. It includes content_index (the position of the completed content part), item_id (the ID of the parent output item), output_index (position of the output item), a part field containing the finished content (which can be ResponseOutputText, ResponseOutputRefusal, or PartReasoningText), a sequence_number for ordering, and a fixed type of "response.content_part.done". The Part type alias is a discriminated union keyed on type. This type is auto-generated from the OpenAI OpenAPI specification by Stainless.

Usage

Import ResponseContentPartDoneEvent when handling streaming events and you need to detect that a specific content part (text, refusal, or reasoning text) has finished streaming.

Code Reference

Source Location

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

Signature

class ResponseContentPartDoneEvent(BaseModel):
    """Emitted when a content part is done."""

    content_index: int
    item_id: str
    output_index: int
    part: Part
    sequence_number: int
    type: Literal["response.content_part.done"]

Import

from openai.types.responses import ResponseContentPartDoneEvent

I/O Contract

Fields

Name	Type	Required	Description
content_index	int	Yes	The index of the content part that is done.
item_id	str	Yes	The ID of the output item that the content part was added to.
output_index	int	Yes	The index of the output item that the content part was added to.
part	Part	Yes	The content part that is done. One of ResponseOutputText, ResponseOutputRefusal, or PartReasoningText.
sequence_number	int	Yes	The sequence number of this event.
type	Literal["response.content_part.done"]	Yes	The type of the event. Always "response.content_part.done".

Part Sub-Types

Type	Discriminator Value	Description
ResponseOutputText	"output_text"	Completed text output from the model.
ResponseOutputRefusal	"refusal"	A refusal response from the model.
PartReasoningText	"reasoning_text"	Reasoning text from the model.

Usage Examples

from openai.types.responses import ResponseContentPartDoneEvent

# Processing streaming events
for event in stream:
    if isinstance(event, ResponseContentPartDoneEvent):
        print(f"Content part {event.content_index} done for item {event.item_id}")
        if event.part.type == "output_text":
            print(f"Text: {event.part.text}")
        elif event.part.type == "refusal":
            print(f"Refusal: {event.part.refusal}")

Related Pages

• Environment:Openai_Openai_python_Python_3_9_Plus