Gemini 3.1 Pro Preview is Google’s advanced reasoning model, designed for complex coding, agentic workflows, and high-context problem solving. It delivers improved software engineering performance, stronger agent reliability, and better token efficiency across demanding tasks. Built on the Gemini 3 multimodal foundation, it supports advanced reasoning across text, images, video, audio, and code, with a 1 million token context window for processing large-scale information and long-running workflows. It delivers improved performance on software engineering benchmarks and real-world coding environments, while enabling more reliable autonomous execution in structured domains such as finance and spreadsheet automation. Gemini 3.1 Pro Preview introduces a medium thinking level to provide better control over the trade-off between intelligence, latency, and cost. With stronger long-horizon reasoning, tool orchestration, and workflow automation capabilities, it is optimized for AI agents, coding assistants, multimodal analysis, enterprise automation, and complex data-driven applications.
Pricing
USD · live rate| Pricing | USD / M |
|---|---|
| Input | $2.00 ≤200K $4.00 >200K |
| Output | $12.00 ≤200K $18.00 >200K |
| Cache hit | $0.20 ≤200K $0.40 >200K |
| Image input | — |
Providers
Same model, multi-channel live comparison · best values highlighted| Provider | Context | Max output | Input /M | Output /M | Cache /M | Latency | Throughput |
|---|---|---|---|---|---|---|---|
| OpenRouter | 1M | 66K | $2.00 ≤200K $4.00 >200K | $12.00 ≤200K $18.00 >200K | $0.20 ≤200K $0.40 >200K | 23136ms | 99 t/s |
| Google Vertex | 1M | 66K | $2.00 ≤200K $4.00 >200K | $12.00 ≤200K $18.00 >200K | $0.20 ≤200K $0.40 >200K | 14049ms | 201 t/s |
Usage trends
API example
Model Center normalizes requests and responses across providers behind one OpenAI-compatible API.
Call this model directly or through the OpenAI SDK — one API key for every model in the catalog.
from openai import OpenAI
client = OpenAI(
base_url="https://router-integration.test.cogfoundry.ai/api/v1",
api_key="$MODEL_CENTER_API_KEY",
)
completion = client.chat.completions.create(
model="google/gemini-3.1-pro-preview",
messages=[{"role": "user", "content": "Which number is larger, 9.11 or 9.8?"}],
stream=True,
)
for chunk in completion:
if chunk.choices and chunk.choices[0].delta.content is not None:
print(chunk.choices[0].delta.content, end="", flush=True)import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://router-integration.test.cogfoundry.ai/api/v1",
apiKey: process.env.MODEL_CENTER_API_KEY,
});
const stream = await client.chat.completions.create({
model: "google/gemini-3.1-pro-preview",
messages: [{ role: "user", content: "Which number is larger, 9.11 or 9.8?" }],
stream: true,
});
for await (const chunk of stream) {
process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}curl https://router-integration.test.cogfoundry.ai/api/v1/chat/completions \
-H "Authorization: Bearer $MODEL_CENTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/gemini-3.1-pro-preview",
"messages": [{"role": "user", "content": "Which number is larger, 9.11 or 9.8?"}],
"stream": true
}'import requests
response = requests.post(
"https://router-integration.test.cogfoundry.ai/api/v1/messages",
headers={"Authorization": "Bearer $MODEL_CENTER_API_KEY", "Content-Type": "application/json"},
json={
"model": "google/gemini-3.1-pro-preview",
"max_tokens": 1024,
"messages": [{"role": "user", "content": "Which number is larger, 9.11 or 9.8?"}],
},
)
print(response.json()["content"][0]["text"])const response = await fetch("https://router-integration.test.cogfoundry.ai/api/v1/messages", {
method: "POST",
headers: {
Authorization: "Bearer $MODEL_CENTER_API_KEY",
"Content-Type": "application/json",
},
body: JSON.stringify({
model: "google/gemini-3.1-pro-preview",
max_tokens: 1024,
messages: [{ role: "user", content: "Which number is larger, 9.11 or 9.8?" }],
}),
});
const data = await response.json();
console.log(data.content[0].text);curl https://router-integration.test.cogfoundry.ai/api/v1/messages \
-H "Authorization: Bearer $MODEL_CENTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/gemini-3.1-pro-preview",
"max_tokens": 1024,
"messages": [{"role": "user", "content": "Which number is larger, 9.11 or 9.8?"}]
}'