OpenAIChat

OpenAI: GPT-5.3 Chat

openai/gpt-5.3-chat

128KContext Window

16KMax Output

Supported Protocols:seedmax_tokensresponse_formatstructured_outputstoolstool_choice

Normal

GPT-5.3 Chat is an update to ChatGPT's most-used model that makes everyday conversations smoother, more useful, and more directly helpful. It delivers more accurate answers with better contextualization and significantly reduces unnecessary refusals, caveats, and overly cautious phrasing that can interrupt conversational flow.

Capabilities

👁 Vision🔧 Function CallingText GenerationCode GenerationAnalysis & ReasoningReasoning

Technical Specs

Input Modality

Text、Image、Text

Output Modality

Text

Arch

—

Default Temperature

0.7

Default Top_P

Pricing

Pay per use, no monthly fees

Billing Type	Unit	Price
Text Input	—	$1.7500/M tokens
Text Output	—	$14.0000/M tokens
Cache Read	—	$0.1750/M tokens
Web Search	—	$0.0100/次

Quick Start

from openai import OpenAI

client = OpenAI(
    base_url="https://api.uniontoken.ai/v1",
    api_key="YOUR_UNIONTOKEN_API_KEY",
)

response = client.chat.completions.create(
    model="openai/gpt-5.3-chat",
    messages=[
        {"role": "user", "content": "Hello!"}
    ],
)

print(response.choices[0].message.content)