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

# Edges & data flow

> How outputs from one node feed into another.

An **edge** is a directed wire from one node to another. The downstream node receives the upstream node's output as part of its prompt context.

Think of it like attaching an image or file to a message in an AI chat — when you connect one node to another, Melius appends the upstream node's data (its text, image, video, or audio) to the end of the downstream node's input. The downstream model sees your prompt *plus* whatever the upstream node produced.

## Edge data types

Edges are typed. The type matches the upstream output:

* `text` — written output from a text node or the literal content of a `custom_text` node.
* `image` — a generated or uploaded image.
* `video` — a generated video clip.
* `audio` — a generated or uploaded audio clip.
* `file` — an uploaded image asset.

Downstream nodes accept only the input types they support — image nodes accept text and image, video nodes accept text, image, and video, etc.

## Creating edges

* **By dragging** — drag from a source node's output handle to a target node's input handle.
* **By @-mention** — type `@` inside a prompt and pick a node. Melius creates an input edge automatically.
* **Programmatically** — see [`edge_create`](/mcp/tools#edges).

## Removing edges

Click an edge to select it, then press `Delete`. Removing the edge does not affect either node's existing versions — only the next run will reflect the change.