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

# Introduction

> Simplex is a browser automation API built for complex form filling.

<video autoPlay loop muted playsInline className="-mt-2">
  <source src="https://simplex.sh/cigna_2.mp4" type="video/mp4" />
</video>

## How it works

Simplex wraps form complexity into a simple API. You build workflows in an interactive editor, then run them deterministically in production.

* **Custom-built web agents** — agents write and execute code to fill forms, handling dropdowns, branching logic, and multi-step flows
* **Automatic form mapping** — discovers which question branches might appear based on your input data
* **Variables and test data** — integrates with your existing databases and context engines
* **Structured outputs** — get structured data back via API (approval status, quote amounts, confirmation numbers)
* **Deterministic production execution** — workflows run as code (fast, cheap, reliable), not LLM inference

<Card title="Quickstart" icon="rocket" href="/docs/get-started/your-first-workflow">
  Build and run your first workflow in minutes.
</Card>