TessellatedShapeCreatorUtils Revit sample code with Command to create a D4

TessellatedShapeCreatorUtils.cs

using Autodesk.Revit.Attributes;
using Autodesk.Revit.DB;
using Autodesk.Revit.UI;
using System;
using System.Collections.Generic;

namespace RevitAddin.Commands
{
    [Transaction(TransactionMode.Manual)]
    public class CommandTessellatedD4 : IExternalCommand
    {
        public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elementSet)
        {
            UIApplication uiapp = commandData.Application;

            Document document = uiapp.ActiveUIDocument.Document;

            var shapeBuilder = TessellatedShapeCreatorUtils.Create(builder =>
            {
                var points = new List<XYZ>(4);
                points.Add(new XYZ(0, 0, 0)); // 0 origin
                points.Add(new XYZ(1, 0, 0)); // 1 right
                points.Add(new XYZ(0, 1, 0)); // 2 back
                points.Add(new XYZ(0, 0, 1)); // 3 top

                var materialId = ElementId.InvalidElementId;
                builder.AddFace(new TessellatedFace(new[] { points[2], points[1], points[0] }, materialId)); // bottom face
                builder.AddFace(new TessellatedFace(new[] { points[0], points[1], points[3] }, materialId)); // front face
                builder.AddFace(new TessellatedFace(new[] { points[1], points[2], points[3] }, materialId)); // diagonal face
                builder.AddFace(new TessellatedFace(new[] { points[2], points[0], points[3] }, materialId)); // left face
            });

            using (Transaction transaction = new Transaction(document))
            {
                transaction.Start("Create");
                var ds = DirectShape.CreateElement(document, new ElementId(BuiltInCategory.OST_GenericModel));
                ds.SetName(ds.Category.Name);
                ds.SetShape(shapeBuilder.GetGeometricalObjects());
                transaction.Commit();
            }

            return Result.Succeeded;
        }
    }

    public static class TessellatedShapeCreatorUtils
    {
        public static TessellatedShapeBuilderResult Create(Action<TessellatedShapeBuilder> actionBuilder)
        {
            TessellatedShapeBuilder builder = new TessellatedShapeBuilder();
            builder.Target = TessellatedShapeBuilderTarget.AnyGeometry;
            builder.Fallback = TessellatedShapeBuilderFallback.Mesh;
            builder.OpenConnectedFaceSet(true);
            actionBuilder?.Invoke(builder);
            builder.CloseConnectedFaceSet();
            builder.Build();
            TessellatedShapeBuilderResult result = builder.GetBuildResult();
            return result;
        }
    }
}

Revit Api Forum: https://forums.autodesk.com/t5/revit-api-forum/brepbuilder-fails-on-very-simple-example/m-p/12017850