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

# Core Concepts

> Understanding the fundamental concepts of VibeFlow

## Overview

VibeFlow lets you build powerful backend workflows visually or through AI. Connect nodes to create APIs, automations, and data pipelines, with a built-in database and optional frontend. Here are the key concepts you need to understand.

## Workflows

A **workflow** is a visual representation of your backend logic. Think of it as a flowchart where each box (node) performs a specific task, and arrows show how data flows between them.

<CardGroup cols={2}>
  <Card title="Visual Logic" icon="sitemap">
    Connect nodes visually instead of writing code
  </Card>

  <Card title="Real-time Testing" icon="bolt">
    Test your workflows instantly as you build
  </Card>
</CardGroup>

***

## Nodes

**Nodes** are the building blocks of workflows. Each node performs a specific function, like fetching data, sending emails, or making decisions.

### Node Categories

<AccordionGroup>
  <Accordion title="Data Nodes">
    Handle database operations and data management

    * **Query**: Fetch data from your database
    * **Mutation**: Create, update, or delete data
    * **Collection**: Work with arrays and collections
  </Accordion>

  <Accordion title="Trigger Nodes">
    Start workflows based on events

    * **Frontend Element (Start Node)**: Connect to UI components and kick off a workflow
    * **Webhook**: Receive incoming HTTP requests from external services
    * **Cron**: Run workflows on a schedule
  </Accordion>

  <Accordion title="Core Nodes">
    Essential building blocks for backend logic

    * **Return**: Send a response back to the caller
    * **HTTP Request**: Call external APIs and services
  </Accordion>

  <Accordion title="Flow Nodes">
    Control how data moves through your workflow

    * **If-Else**: Branch logic based on conditions
    * **Edit Fields**: Transform and reshape data between nodes
    * **Code**: Write custom logic when you need full control
    * **For Loop**: Iterate over lists of items
  </Accordion>

  <Accordion title="AI & Integrations">
    Add intelligence and connect to third-party services

    * **Agent (AI)**: AI-powered processing and decisions using LLMs
    * **MCP Tools**: Connect to Model Context Protocol tool servers
    * **Stripe**: Accept payments and manage subscriptions
    * **Email**: Send emails via Resend
  </Accordion>
</AccordionGroup>

***

## Connections

**Connections** are the arrows between nodes that show how data flows through your workflow. Data from one node becomes input for the next node.

## Variables & Data

VibeFlow automatically passes data between nodes, but you can also use **variables** to store and reuse data throughout your workflow.

### Data Sources:

* **Frontend Input**: Data from forms, user interactions
* **Database**: Information stored in your database
* **API Responses**: Data from external services
* **Node Output**: Results from previous nodes in the workflow

***

## Credits & Features

VibeFlow provides **free credits** to get you started with all features included.

***

## Best Practices

<CardGroup cols={2}>
  <Card title="Name Things Clearly" icon="tag">
    Use descriptive names for workflows and nodes
  </Card>

  <Card title="Test Early & Often" icon="flask">
    Test workflows as you build them
  </Card>
</CardGroup>

***

## Next Steps

Now that you understand the core concepts, here's what to do next:

<CardGroup cols={2}>
  <Card title="Quick Start Guide" icon="play" href="/quickstart">
    Build your first workflow in 5 minutes
  </Card>

  <Card title="Node Reference" icon="puzzle" href="/nodes/query-node">
    Learn about all available nodes
  </Card>
</CardGroup>