Gemini 3.1 Pro Preview API

Google's Gemini 3.1 Pro Preview, through an OpenAI-compatible API. Providers quote it on an open exchange, and each request goes to the offer with the lowest estimated charge that meets your rules.

Providers compete for each request. The exchange ranks the offers that meet your rules by estimated charge. It fixes your maximum charge before the first token, and you pay for the tokens that the model uses.
The OpenAI and Anthropic APIs. Use the OpenAI or Anthropic SDK that you have. Set the base URL and your key, and send gemini-3.1-pro-preview as the model.
Your data rules. Send x-liquid-retention: none and only offers whose provider does not keep your content compete for the request.

Facts

Model name: gemini-3.1-pro-preview
Maker: Google
Context window: 200K tokens
Input price: $2.004 per million tokens
Output price: $12.024 per million tokens
Providers: 1 independent provider
Regions: us

Providers

Architect: us, $2.004 input and $12.024 output per million tokens, $0.200 cache read, $0.376 cache write per million tokens, 200K tokens of context

Scores

HLE: 47.0, #15 of 273
GPQA: 94.1, #3 of 250
AA-LCR: 82.0, #28 of 237
SciCode: 58.7, #14 of 123
Terminal-Bench Hard: 53.8, #6 of 166
τ²-Bench: 95.6, #14 of 169
IFBench: 77.1, #10 of 178
SimpleQA Verified: 73.5, #4 of 126

Scores: Artificial Analysis (https://artificialanalysis.ai/)

Scores: Epoch AI, 'Capabilities & Benchmarking' (https://epoch.ai/benchmarks)

Request

curl https://router.inference.ai.exchange/v1/chat/completions \
  -H "Authorization: Bearer $LIQUID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-3.1-pro-preview",
    "messages": [{"role":"user","content":"Say hello."}]
  }'

Questions

What is Gemini 3.1 Pro Preview?: Served by intent-router: each job goes to the cheapest healthy upstream for this model.
How much does Gemini 3.1 Pro Preview cost?: Offers now ask $2.004 per million input tokens and $12.024 per million output tokens. A job pays for the tokens it uses. The exchange picks the cheapest eligible offer.
What is the context length of Gemini 3.1 Pro Preview?: The largest offer takes 200,000 input tokens. A smaller offer can take less. The exchange skips an offer that cannot take your message.
What can Gemini 3.1 Pro Preview do?: Its providers list Audio input, Documents, Vision, Video input, Reasoning effort, JSON object, JSON schema, Frequency penalty, Logit bias, Log probabilities, Min-p sampling, Presence penalty, Repetition penalty, Seed, Stop sequences, Top-k sampling, Top-p sampling, Text, Tools.
What inputs and outputs does Gemini 3.1 Pro Preview support?: Text · Audio · Files · Images · Video → Text.
Which providers serve Gemini 3.1 Pro Preview?: 1 independent provider quote it now, with 1 offer. The table above ranks them by the cost of a typical job.
How do I call Gemini 3.1 Pro Preview?: Send "gemini-3.1-pro-preview" as the model in an OpenAI or Anthropic request. The API section links to setup steps for each client.
When was Gemini 3.1 Pro Preview listed?: The exchange first listed it on 10/8/2026. This is not its release date.