Invoke a child ActionFlow from a parent graph. The child uses a Start Subflow node; the parent uses a SubFlow utility node.

Subflow

A subflow is a child ActionFlow started by another flow, not by a webhook or API key.

Two nodes

Node	Where	Role
Start Subflow (`startSubflow`)	Child flow	The child's only start node. Marks the graph as callable from a parent.
SubFlow (`subflow`)	Parent flow	Utility node that selects and runs the child, then exposes `outputData` and `status`.

Create the child flow. Choose Start Subflow in the start-node picker.
Save the child. It must pass ActionFlow requirements like any other flow.
In the parent, add a SubFlow node from the utility category and select the child.
Map parent data into the child and use the child's outputData downstream.

The child's run is recorded with triggerSource subflow.

One start node per flow. A child that starts with Start Subflow is not also a webhook or scheduled graph.
The child is still an organization flow. Credentials, credits, and validation apply on the child run.
Do not reuse a session-style mental model. This is a nested flow run, not an agent session.