Google: Gemini 3.1 Pro Preview Custom Tools

google/gemini-3.1-pro-preview-customtools

1049KContext Window

66KMax Output

Supported Protocols:reasoninginclude_reasoningmax_tokenstemperaturetop_pseedresponse_formattoolstool_choicestopstructured_outputs

Normal

Gemini 3.1 Pro Preview Custom Tools is a variant of Gemini 3.1 Pro that improves tool selection behavior by preventing overuse of a general bash tool when more efficient third-party or user-defined functions are available. This specialized preview endpoint significantly increases function calling reliability and ensures the model selects the most appropriate tool in coding agents and complex, multi-tool workflows. It retains the core strengths of Gemini 3.1 Pro, including multimodal reasoning across text, image, video, audio, and code, a 1M-token context window, and strong software engineering performance.

Capabilities

👁 Vision🧠 Reasoning🔧 Function CallingText GenerationCode GenerationAnalysis & ReasoningReasoning

Technical Specs

Input Modality

Text、Audio、Image、Video、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	—	$2.0000/M tokens
Text Output	—	$12.0000/M tokens
Cache Read	—	$0.2000/M tokens
Cache Write 1h	—	$0.3750/M tokens
Cache Write	—	$0.3750/M tokens
Reasoning	—	$2.0000/M tokens
Audio Cache Read	—	$0.2000/M tokens
Image Input	—	< $0.001/张
Audio Input	—	$2.0000/分钟
Web Search	—	$0.0140/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="google/gemini-3.1-pro-preview-customtools",
    messages=[
        {"role": "user", "content": "Hello!"}
    ],
)

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