> ## Documentation Index
> Fetch the complete documentation index at: https://narev.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Variants

> A Narev variant captures a model choice, system prompt, and inference parameters so you can A/B test LLM configurations against your own benchmarks.

## What are variants?

Variants are your execution configurations. It's a combination of model, system prompt, and parameters, such as temperature and max tokens

## When do you use variants?

Use variants when you want to test how different model and router configurations perform on the same benchmark. Attach multiple variants to a benchmark to compare outcomes.

## How do variants work?

You attach variants to benchmarks. The benchmark provides the request data, and the variant provides the execution logic. This separation lets you test multiple configurations on the same prompts.