What inputs does Gemini 3.1 Pro Preview (Custom Tools) accept?

It accepts text, audio, images, video and PDFs and files and returns text. Reasoning effort ("thinking") is configurable.

What is the context window of Gemini 3.1 Pro Preview (Custom Tools)?

Up to 1.0M tokens, suitable for very long documents and large codebases.

How much does Gemini 3.1 Pro Preview (Custom Tools) cost?

Usage-based pricing: $2/M in · $12/M out.

What is Gemini 3.1 Pro Preview (Custom Tools) good for?

Reasoning, coding, math and general chat, plus document and image understanding. Enable thinking for hard multi-step problems.

How do I access Gemini 3.1 Pro Preview (Custom Tools) from inside Iran?

Create an account on Hormouz and generate an API key. Hormouz provides stable access from inside Iran via an OpenAI-compatible API.

Google: Gemini 3.1 Pro Preview Custom Tools: AI model

Gemini 3.1 Pro Preview (Custom Tools) is a Google multimodal model for reasoning, coding and everyday chat, with a 1.0M-token context window. Available via Hormouz with stable access from inside Iran.

Context window:: 1,048,576 tokens
Input:: $2/1M tokens
Output:: $12/1M tokens
Type:: text, audio, image, video

Vision
Tools
Streaming
Long context

Thinking levels: Always thinks · high · medium · low

Gemini 3.1 Pro Preview (Custom Tools) is a Google Gemini-family model built for reasoning, coding, mathematics and general chat. It supports configurable "thinking" (reasoning effort levels) so you can trade cost and latency for accuracy on hard tasks. It accepts text, audio, images, video and PDFs and files and returns text, with a context window of up to 1.0M tokens.

This variant improves tool-selection behaviour, favouring purpose-built functions over a generic shell tool. That makes it more reliable in coding agents and multi-tool workflows, while keeping the core Pro strengths: multimodal reasoning and a large context window.

Pricing is usage-based at $2/M in · $12/M out. Gemini 3.1 Pro Preview (Custom Tools) is served through Hormouz behind an OpenAI-compatible API, with stable access from inside Iran.

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...

Quickstart

curl https://api.hormouz.net/v1/chat/completions \
  -H "Authorization: Bearer ng-YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/gemini-3.1-pro-preview-customtools",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Specs

Vendor	Google
Type	Text, Audio, Image, Video
Context window	1,048,576 tokens
Pricing	$2.00/M in · $12.00/M out
API	Chat Completions
Capabilities	Streaming · Vision · Tools

Code example

cURL

curl https://api.hormouz.net/v1/chat/completions \
  -H "Authorization: Bearer ng-YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "google/gemini-3.1-pro-preview-customtools",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Python

from openai import OpenAI
client = OpenAI(api_key="ng-YOUR_API_KEY", base_url="https://api.hormouz.net/v1")
response = client.chat.completions.create(
    model="google/gemini-3.1-pro-preview-customtools",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)

JavaScript

import OpenAI from "openai";
const client = new OpenAI({ apiKey: "ng-YOUR_API_KEY", baseURL: "https://api.hormouz.net/v1" });
const response = await client.chat.completions.create({
  model: "google/gemini-3.1-pro-preview-customtools",
  messages: [{ role: "user", content: "Hello!" }],
});
console.log(response.choices[0].message.content);

Buy the Google: Gemini 3.1 Pro Preview Custom Tools API, paid in rial

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One Hormouz key reaches Google: Gemini 3.1 Pro Preview Custom Tools and 600+ other models, and you pay only for what you use.
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FAQ

What inputs does Gemini 3.1 Pro Preview (Custom Tools) accept?: It accepts text, audio, images, video and PDFs and files and returns text. Reasoning effort ("thinking") is configurable.
What is the context window of Gemini 3.1 Pro Preview (Custom Tools)?: Up to 1.0M tokens, suitable for very long documents and large codebases.
How much does Gemini 3.1 Pro Preview (Custom Tools) cost?: Usage-based pricing: $2/M in · $12/M out.
What is Gemini 3.1 Pro Preview (Custom Tools) good for?: Reasoning, coding, math and general chat, plus document and image understanding. Enable thinking for hard multi-step problems.
How do I access Gemini 3.1 Pro Preview (Custom Tools) from inside Iran?: Create an account on Hormouz and generate an API key. Hormouz provides stable access from inside Iran via an OpenAI-compatible API.

Updated 2026-10-13