Setting Up Allowed Connections

How to define which Node Types can be connected by which Relationship Types.

Allowed Connections define which Node Types can be connected by which Relationship Types. You must set these up before you can draw relationships on the canvas.

Step-by-Step

First, make sure you have at least one Relationship Type and two Node Types created
Select the Relationship Type in the Model Navigator (e.g., "runs_on")
Open the Properties Panel (right side)
Find the Allowed Connections section
Click + Add Allowed Connection
Select the Source Node Type (e.g., "Application")
Select the Target Node Type (e.g., "Server")
The allowed connection is saved immediately

Adding Multiple Allowed Connections

A single Relationship Type can have many Allowed Connections:

"depends_on": Application → Application, Application → Service, Service → Service
"manages": Person → Person, Person → Team

Just repeat the steps above for each valid combination.

Directionality

Allowed Connections are directional:

Application → runs_on → Server means you can draw from Application to Server
It does NOT automatically allow Server → runs_on → Application
If you need both directions, add both as separate Allowed Connections

Removing an Allowed Connection or a Relationship Type

Deleting in the metamodel always tells you what goes with it, and one undo brings it all back.

One allowed connection: select it under its relationship type in the Model Navigator and choose Delete allowed connection, or right-click its connector on a metamodel diagram and choose Delete connection Source → Target. Relationships that used this connection are removed too, and the dialog lists them first.
The whole relationship type: on the metamodel diagram, choose Delete Relationship Type from Model. If the type is allowed between several pairs of node types, the dialog says how many and offers Delete only this connection instead.
Just the picture: Delete from Diagram removes the connector from this diagram and leaves the metamodel untouched.

On a metamodel diagram the right-click menu lists these from smallest to largest: Delete from Diagram, Delete connection …, Delete Relationship Type from Model.

Verifying Your Setup

To check if connections are set up correctly:

Place two nodes of the relevant types on a diagram
Try drawing a relationship between them
If the popup shows available relationship types, your Allowed Connections are working
If nothing happens, review the Allowed Connections on your Relationship Types