# Editor.MeshEditor.PrimitiveBuilder.PolygonMesh.AddVertex

```csharp
int AddVertex(Vector3 position)
```

Adds a new vertex to the end of the [Editor.MeshEditor.PrimitiveBuilder.PolygonMesh.Vertices](/api/Editor.MeshEditor.PrimitiveBuilder.PolygonMesh/Vertices) list.

### Parameters

- `position` (`Vector3`): Position of the vertex to add.

### Returns

`int`: The index of the newly added vertex.

Declared in [Editor.MeshEditor.PrimitiveBuilder.PolygonMesh](/api/Editor.MeshEditor.PrimitiveBuilder.PolygonMesh).
Assembly: `Sandbox.Tools`.