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

# Loop node

> Repeat a set of steps once per twin or per waypoint, then continue once every item is done.

The **Loop** (`loop`) node repeats the steps connected after it, once per item
in a list. Use it to run the same work across several robots — or to send one
robot to several places — without copying the steps.

## Two branches

A Loop has two outputs on the canvas:

| Output             | When it runs                                                         |
| ------------------ | -------------------------------------------------------------------- |
| **For each item**  | Once per item, with that item available to the steps on this branch. |
| **After the loop** | Once, after the last item — and only if every item succeeded.        |

Drag from the branch you want. Steps on **For each item** are the loop body;
steps on **After the loop** run once, so that is where a "report that every
robot is parked" step belongs.

<Note>
  **After the loop** is a success continuation. If any item fails, or the list is
  empty, that branch is skipped and marked as such in the run history.
</Note>

## Picking what to repeat over

In **Simple** mode, choose a **Type** and then pick the items:

* **Twin** — "do this to each of these robots."
* **Waypoint** — "send this robot to each of these places."

**Advanced** mode hands you the raw `array_data` input, so you can fan out over
a list computed by an upstream node.

## Using the item in a step

A step inside the loop body takes its value from the iteration rather than from
its own picker. Open the step and set its source to **From loop item**:

| Node                                                             | What binds to the item                             |
| ---------------------------------------------------------------- | -------------------------------------------------- |
| Recorder, Data Source, Create Attachment, Send Pose, Move to GPS | The twin it acts on                                |
| Move Twin                                                        | The twin it moves, **or** the waypoint it moves to |

The control appears on any step inside the loop body, however many steps down
the chain it sits.

<Note>
  Send Pose keeps its own twin picker when bound. The pose is authored against
  the twin you pick — its joint names, limits and saved poses — and then sent to
  each item of the loop.
</Note>

## Nesting loops

A Loop can sit inside another Loop's body: "for each station, for each robot at
that station." A step inside the inner loop can take its value from *either*
loop — each is offered by name, so you can address the station and the robot in
the same step.

## Limits

* **Edge workflows** compile one copy of the body per item, so the list has to
  be a fixed value. With nested loops the copies multiply, and the total is
  capped — shorten one of the lists if you hit the limit.
* A list computed at run time works in the cloud, where the loop iterates as it
  runs. Set the workflow to run in the cloud for that shape.