Google

Google: Gemini 3.1 Pro Preview Custom Tools

preview

Gemini 3.1 Pro Preview Custom Tools is available through Everstack's OpenAI-compatible gateway with routing, fallback, retries, and observability.

gemini-3.1-pro-preview-customtoolsgemini-proreleased Feb 19, 2026
ProviderQuick start
Context
1.0M
tokens
Max output
65.5K
tokens
Input
$2.00
per 1M
Output
$12.00
per 1M

Activity

Daily period usage
Aggregated managed Everstack traffic. Buckets below 5 tenants or 100 requests are withheld.

Providers

ProviderContextInput /MOutput /M
Google
Google
1.0M$2.00$12.00

Pricing

ItemPriceUnit
Input$2.00per 1M tokens
Output$12.00per 1M tokens
Cache read$0.20per 1M tokens

Performance

Reliability

Compare

Compare usage and performance
Place this model beside up to three other catalog models.

Capabilities

Capabilities
Modalities
Input
Output
Details
Model ID
gemini-3.1-pro-preview-customtools
Family
gemini-pro
Status
preview
Knowledge
Jan 1, 2025
Released
Feb 19, 2026
Gateway Config
API
2024-01-01
Auth
GOOGLE_API_KEY
Discovery
static
Provider type
static

Quick Start

index.ts
import Everstack from "@everstack/node";const client = new Everstack({  apiKey: process.env.EVERSTACK_API_KEY!,  baseUrl: "https://{instance}.{region}.everstack.ai",});const completion = await client.chat.completions.create({  model: "@google/gemini-3.1-pro-preview-customtools",  messages: [{ role: "user", content: "Explain vector cache routing." }],});console.log(completion.choices[0]?.message?.content);

Endpoint

Base URL
https://generativelanguage.googleapis.com/v1
Chat completions
https://generativelanguage.googleapis.com/v1/chat/completions
Model
gemini-3.1-pro-preview-customtools
Auth env
GOOGLE_API_KEY

Gemini 3.1 Pro Preview Custom Tools FAQ

How much does the Gemini 3.1 Pro Preview Custom Tools API cost?

Through Google, Gemini 3.1 Pro Preview Custom Tools costs $2.00 per 1M input tokens and $12.00 per 1M output tokens.

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

Gemini 3.1 Pro Preview Custom Tools accepts up to 1.0M tokens of context and returns up to 65.5K output tokens on Google.

What can Gemini 3.1 Pro Preview Custom Tools do?

Gemini 3.1 Pro Preview Custom Tools supports chat, function calling, image input and reasoning. It accepts text, image, video, audio and PDF input.

How do I call Gemini 3.1 Pro Preview Custom Tools through Everstack?

Point any OpenAI-compatible SDK at your Everstack gateway and set the model to @google/gemini-3.1-pro-preview-customtools. Everstack adds retries, provider fallback, caching, per-tenant budgets and OpenTelemetry traces for every request.