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

# Introduction

> What is the Zelinqa NBQ Engine and how does it work?

> The intelligence behind every right question. Zelinqa builds the NBQ Engine — the decision layer that tells any AI agent or application which question to ask next, so every conversation collects exactly what it needs.

The **NBQ Engine** (Next Best Question Engine) is a service that returns the single most relevant question to ask a user at each turn of a conversation.

Instead of building your own question-routing logic, your application calls one API endpoint and the engine decides — in real time — which question to ask next, based on what has already been said and what you still need to learn.

## How it works

<Steps>
  <Step title="Configure in the NBQ Studio">
    Your team sets up questions, rules, and behavior in the Zelinqa NBQ Studio — no coding required.
  </Step>

  <Step title="Your application calls the API">
    Each time your application needs to ask the user something, it sends the current conversation context to the NBQ Engine.
  </Step>

  <Step title="The engine returns the best question">
    The API responds with the most relevant next question, or signals that the conversation is complete.
  </Step>
</Steps>

## Two components

<CardGroup cols={2}>
  <Card title="NBQ Studio" icon="sliders" href="/en/backoffice/overview">
    A no-code web interface where your team configures questions, rules, tone, and generates API keys.
  </Card>

  <Card title="API" icon="bolt" href="/en/api-reference/overview">
    A single stateless REST endpoint your developers call to get the next question in real time.
  </Card>
</CardGroup>

## Key facts

* The API is **stateless** — you send the full conversation context with every request.
* The engine returns **one question per call**, the most relevant one.

<Note>
  You do not need to write any question-selection logic. The NBQ Engine handles that based on your NBQ Studio configuration.
</Note>