Google launched the Gemini Decisions API on November 11, powered by a model called gemini-decision-1 that scores a fixed set of options in a single forward pass and returns probabilities and confidence scores instead of generated text. One request takes up to 256,000 tokens of text, images, audio, video or PDFs and up to 1,000 independent questions, each a yes/no check, a multiple-choice question with up to 255 options or a rubric score, with Google quoting 150 to 250 milliseconds end to end. Pricing is $0.10 per million input tokens and nothing for output, with shared input billed once per request; Google says it is nearly five times cheaper than Gemini 3.5 Flash-Lite on its own benchmark suite. It is available in AI Studio with a free tier, and OpenAI launched a comparable Decisions API on GPT-6 Luna in October at the same starting price.
DevelopersRouting, tool selection, policy checks and grading are the calls that currently burn Flash-class tokens inside every agent loop. This is a drop-in for most of them, with integrations landing in OpenRouter, LangChain, LiteLLM and Pydantic AI.
ML engineersA classifier head with calibrated probabilities beats parsing JSON out of a generated answer. Google claims the lowest calibration error in its comparison; test that claim on your own labels before trusting the confidence scores.
FinanceGoogle says Gemini Notebook cut latency for everyday queries by up to 40% by routing with this model. If routing is cheaper than the models it routes to, the cost-per-task curve bends down for everyone.
SecurityGoogle uses it in Search as a safety layer that flags adversarial MCP tool behaviour. A cheap, fast judge that cannot generate text is a useful guard in front of agents that can.
ExecutivesTwo vendors now sell decisions as a product separate from text. Expect your AI bill to split into generation, retrieval and decisions, each priced differently.
BeginnersInstead of writing an answer, this model picks from options you give it, very fast and very cheaply. It is for the thousands of small yes-or-no choices inside AI software, not for chatting.