Implementation:Openai Openai python Shared Chat Model

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

Overview

Concrete tool for defining the literal type of all chat-compatible model identifiers provided by the openai-python SDK.

Description

ChatModel is a TypeAlias defined as a Literal union of all known chat-compatible model identifier strings. It covers the full range of OpenAI chat models across multiple generations:

• GPT-5.x series - gpt-5.2, gpt-5.2-pro, gpt-5.1, gpt-5.1-codex, gpt-5.1-mini, gpt-5, gpt-5-mini, gpt-5-nano and their dated variants.
• GPT-4.1 series - gpt-4.1, gpt-4.1-mini, gpt-4.1-nano and their dated variants.
• O-series reasoning models - o4-mini, o3, o3-mini, o1, o1-preview, o1-mini and their dated variants.
• GPT-4o series - gpt-4o, gpt-4o-audio-preview, gpt-4o-mini-audio-preview, gpt-4o-search-preview, gpt-4o-mini-search-preview, chatgpt-4o-latest, codex-mini-latest, gpt-4o-mini and dated variants.
• GPT-4 legacy series - gpt-4-turbo, gpt-4, gpt-4-32k and their dated variants.
• GPT-3.5 series - gpt-3.5-turbo, gpt-3.5-turbo-16k and dated variants.

Usage

Import ChatModel when you need strict type checking for model identifiers accepted by the Chat Completions API.

Code Reference

Source Location

• Repository: openai-python
• File: src/openai/types/shared/chat_model.py

Signature

ChatModel: TypeAlias = Literal[
    "gpt-5.2",
    "gpt-5.2-2025-12-11",
    "gpt-5.2-chat-latest",
    "gpt-5.2-pro",
    "gpt-5.2-pro-2025-12-11",
    "gpt-5.1",
    "gpt-5.1-2025-11-13",
    "gpt-5.1-codex",
    "gpt-5.1-mini",
    "gpt-5.1-chat-latest",
    "gpt-5",
    "gpt-5-mini",
    "gpt-5-nano",
    # ... (73 total literal values)
    "gpt-3.5-turbo-0125",
    "gpt-3.5-turbo-16k-0613",
]

Import

from openai.types.shared import ChatModel

I/O Contract

Model Families

Family	Example Identifiers	Description
GPT-5.2	gpt-5.2, gpt-5.2-pro, gpt-5.2-2025-12-11	Latest generation models.
GPT-5.1	gpt-5.1, gpt-5.1-codex, gpt-5.1-mini	Previous generation with codex variant.
GPT-5	gpt-5, gpt-5-mini, gpt-5-nano	Base GPT-5 models in multiple sizes.
GPT-4.1	gpt-4.1, gpt-4.1-mini, gpt-4.1-nano	GPT-4.1 generation models.
O-series	o4-mini, o3, o3-mini, o1, o1-mini	Reasoning-focused models.
GPT-4o	gpt-4o, gpt-4o-mini, chatgpt-4o-latest	Optimized GPT-4 variants with audio and search.
GPT-4	gpt-4-turbo, gpt-4, gpt-4-32k	Legacy GPT-4 models.
GPT-3.5	gpt-3.5-turbo, gpt-3.5-turbo-16k	Legacy GPT-3.5 models.

Usage Examples

from openai import OpenAI
from openai.types.shared import ChatModel

def chat(model: ChatModel, message: str) -> str:
    """Type-safe chat using only known chat model identifiers."""
    client = OpenAI()
    response = client.chat.completions.create(
        model=model,
        messages=[{"role": "user", "content": message}],
    )
    return response.choices[0].message.content

# Type checker validates the model string
result = chat("gpt-4o", "Explain Python type aliases.")

Related Pages

• Environment:Openai_Openai_python_Python_3_9_Plus