public sealed class ShapeDescription : Description 

{
  // Must be called within QueuedTask.Run
  void CreateFeatureDatasetWithFeatureClassSnippet(Geodatabase geodatabase)
  {
    // Creating a FeatureDataset named as 'Parcel_Information' and a FeatureClass with name 'Parcels' in one operation
    string featureDatasetName = "Parcel_Information";
    string featureClassName = "Parcels";

    SchemaBuilder schemaBuilder = new SchemaBuilder(geodatabase);

    // Create a FeatureDataset token
    FeatureDatasetDescription featureDatasetDescription = new FeatureDatasetDescription(featureDatasetName, SpatialReferences.WGS84);
    FeatureDatasetToken featureDatasetToken = schemaBuilder.Create(featureDatasetDescription);

    // Create a FeatureClass description
    FeatureClassDescription featureClassDescription = new FeatureClassDescription(featureClassName,
      new List<FieldDescription>()
      {
          new FieldDescription("Id", FieldType.Integer),
          new FieldDescription("Address", FieldType.String)
      },
      new ShapeDescription(GeometryType.Point, SpatialReferences.WGS84));

    // Create a FeatureClass inside a FeatureDataset
    FeatureClassToken featureClassToken = schemaBuilder.Create(
      new FeatureDatasetDescription(featureDatasetToken),
      featureClassDescription);

    // Build status
    bool buildStatus = schemaBuilder.Build();

    // Build errors
    if (!buildStatus)
    {
      IReadOnlyList<string> errors = schemaBuilder.ErrorMessages;
    }
  }
}

{
  // Must be called within QueuedTask.Run
  void CreateFeatureClassInsideFeatureDatasetSnippet(Geodatabase geodatabase)
  {
    // Creating a FeatureClass named as 'Tax_Jurisdiction' in existing FeatureDataset with name 'Parcels_Information'
    string featureDatasetName = "Parcels_Information";
    string featureClassName = "Tax_Jurisdiction";

    // Create a FeatureClass description
    FeatureClassDescription featureClassDescription = new FeatureClassDescription(featureClassName,
      new List<FieldDescription>()
      {
          new FieldDescription("Tax_Id", FieldType.Integer),
          new FieldDescription("Address", FieldType.String)
      },
      new ShapeDescription(GeometryType.Point, SpatialReferences.WGS84));

    FeatureDatasetDefinition featureDatasetDefinition = geodatabase.GetDefinition<FeatureDatasetDefinition>(featureDatasetName);

    SchemaBuilder schemaBuilder = new SchemaBuilder(geodatabase);

    // Create a FeatureClass inside a FeatureDataset using a FeatureDatasetDefinition
    schemaBuilder.Create(new FeatureDatasetDescription(featureDatasetDefinition), featureClassDescription);

    // Build status
    bool buildStatus = schemaBuilder.Build();

    // Build errors
    if (!buildStatus)
    {
      IReadOnlyList<string> errors = schemaBuilder.ErrorMessages;
    }
  }
}

{
  // Must be called within QueuedTask.Run
  void CreateStandAloneAnnotationFeatureClass(
    Geodatabase geodatabase, SpatialReference spatialReference)
  {
    // Creating a Cities annotation feature class
    // with following user defined fields
    // Name 
    // GlobalID

    // Annotation feature class name
    string annotationFeatureClassName = "CitiesAnnotation";

    // Create user defined attribute fields for annotation feature class 
    FieldDescription globalIDFieldDescription = FieldDescription.CreateGlobalIDField();
    FieldDescription nameFieldDescription = FieldDescription.CreateStringField("Name", 255);

    // Create a list of all field descriptions
    List<FieldDescription> fieldDescriptions = new List<FieldDescription>
        { globalIDFieldDescription, nameFieldDescription };

    // Create a ShapeDescription object
    ShapeDescription shapeDescription = new ShapeDescription(GeometryType.Polygon, spatialReference);

    // Create general placement properties for Maplex engine 
    CIMMaplexGeneralPlacementProperties generalPlacementProperties =
      new CIMMaplexGeneralPlacementProperties
      {
        AllowBorderOverlap = true,
        PlacementQuality = MaplexQualityType.High,
        DrawUnplacedLabels = true,
        InvertedLabelTolerance = 1.0,
        RotateLabelWithDisplay = true,
        UnplacedLabelColor = new CIMRGBColor
        {
          R = 0,
          G = 255,
          B = 0,
          Alpha = 0.5f // Green
        }
      };

    // Create general placement properties for Standard engine

    //CIMStandardGeneralPlacementProperties generalPlacementProperties =
    //  new CIMStandardGeneralPlacementProperties
    //  {
    //    DrawUnplacedLabels = true,
    //    InvertedLabelTolerance = 3.0,
    //    RotateLabelWithDisplay = true,
    //    UnplacedLabelColor = new CIMRGBColor
    //    {
    //      R = 255, G = 0, B = 0, Alpha = 0.5f // Red
    //    } 
    //   };


    // Create annotation  label classes
    // Green label
    CIMLabelClass greenLabelClass = new CIMLabelClass
    {
      Name = "Green",
      ExpressionTitle = "Expression-Green",
      ExpressionEngine = LabelExpressionEngine.Arcade,
      Expression = "$feature.OBJECTID",
      ID = 1,
      Priority = 0,
      Visibility = true,
      TextSymbol = new CIMSymbolReference
      {
        Symbol = new CIMTextSymbol()
        {
          Angle = 45,
          FontType = FontType.Type1,
          FontFamilyName = "Tahoma",
          FontEffects = FontEffects.Normal,
          HaloSize = 2.0,

          Symbol = new CIMPolygonSymbol
          {
            SymbolLayers = new CIMSymbolLayer[]
            {
                new CIMSolidFill
                {
                  Color = CIMColor.CreateRGBColor(0, 255, 0)
                }
            },
            UseRealWorldSymbolSizes = true
          }
        },
        MaxScale = 0,
        MinScale = 0,
        SymbolName = "TextSymbol-Green"
      },
      StandardLabelPlacementProperties = new CIMStandardLabelPlacementProperties
      {
        AllowOverlappingLabels = true,
        LineOffset = 1.0
      },
      MaplexLabelPlacementProperties = new CIMMaplexLabelPlacementProperties
      {
        AlignLabelToLineDirection = true,
        AvoidPolygonHoles = true
      }
    };

    // Blue label
    CIMLabelClass blueLabelClass = new CIMLabelClass
    {
      Name = "Blue",
      ExpressionTitle = "Expression-Blue",
      ExpressionEngine = LabelExpressionEngine.Arcade,
      Expression = "$feature.OBJECTID",
      ID = 2,
      Priority = 0,
      Visibility = true,
      TextSymbol = new CIMSymbolReference
      {
        Symbol = new CIMTextSymbol()
        {
          Angle = 45,
          FontType = FontType.Type1,
          FontFamilyName = "Consolas",
          FontEffects = FontEffects.Normal,
          HaloSize = 2.0,

          Symbol = new CIMPolygonSymbol
          {
            SymbolLayers = new CIMSymbolLayer[]
            {
                new CIMSolidFill
                {
                  Color = CIMColor.CreateRGBColor(0, 0, 255)
                }
            },
            UseRealWorldSymbolSizes = true
          }
        },
        MaxScale = 0,
        MinScale = 0,
        SymbolName = "TextSymbol-Blue"
      },
      StandardLabelPlacementProperties = new CIMStandardLabelPlacementProperties
      {
        AllowOverlappingLabels = true,
        LineOffset = 1.0
      },
      MaplexLabelPlacementProperties = new CIMMaplexLabelPlacementProperties
      {
        AlignLabelToLineDirection = true,
        AvoidPolygonHoles = true
      }
    };

    // Create a list of labels
    List<CIMLabelClass> labelClasses = new List<CIMLabelClass> { greenLabelClass, blueLabelClass };

    // Create an annotation feature class description object to describe the feature class to create
    AnnotationFeatureClassDescription annotationFeatureClassDescription =
      new AnnotationFeatureClassDescription(annotationFeatureClassName, fieldDescriptions, shapeDescription,
        generalPlacementProperties, labelClasses)
      {
        IsAutoCreate = true,
        IsSymbolIDRequired = false,
        IsUpdatedOnShapeChange = true
      };

    // Create a SchemaBuilder object
    SchemaBuilder schemaBuilder = new SchemaBuilder(geodatabase);

    // Add the creation of the Cities annotation feature class to the list of DDL tasks
    schemaBuilder.Create(annotationFeatureClassDescription);

    // Execute the DDL
    bool success = schemaBuilder.Build();

    // Inspect error messages
    if (!success)
    {
      IReadOnlyList<string> errorMessages = schemaBuilder.ErrorMessages;
      //etc.
    }
  }
}

{
  // Must be called within QueuedTask.Run
  void CreateFeatureLinkedAnnotationFeatureClass(Geodatabase geodatabase,
    SpatialReference spatialReference)
  {
    // Creating a feature-linked annotation feature class between water pipe and valve in water distribution network
    // with following user defined fields
    // PipeName 
    // GlobalID

    // Annotation feature class name
    string annotationFeatureClassName = "WaterPipeAnnotation";

    // Create user defined attribute fields for annotation feature class
    FieldDescription pipeGlobalID = FieldDescription.CreateGlobalIDField();
    FieldDescription nameFieldDescription = FieldDescription.CreateStringField("Name", 255);

    // Create a list of all field descriptions
    List<FieldDescription> fieldDescriptions = new List<FieldDescription>
        { pipeGlobalID, nameFieldDescription };

    // Create a ShapeDescription object
    ShapeDescription shapeDescription = new ShapeDescription(GeometryType.Polygon, spatialReference);

    // Create general placement properties for Maplex engine 
    CIMMaplexGeneralPlacementProperties generalPlacementProperties = new CIMMaplexGeneralPlacementProperties
    {
      AllowBorderOverlap = true,
      PlacementQuality = MaplexQualityType.High,
      DrawUnplacedLabels = true,
      InvertedLabelTolerance = 1.0,
      RotateLabelWithDisplay = true,
      UnplacedLabelColor = new CIMRGBColor
      {
        R = 255,
        G = 0,
        B = 0,
        Alpha = 0.5f
      }
    };

    // Create annotation  label classes
    // Green label
    CIMLabelClass greenLabelClass = new CIMLabelClass
    {
      Name = "Green",
      ExpressionTitle = "Expression-Green",
      ExpressionEngine = LabelExpressionEngine.Arcade,
      Expression = "$feature.OBJECTID",
      ID = 1,
      Priority = 0,
      Visibility = true,
      TextSymbol = new CIMSymbolReference
      {
        Symbol = new CIMTextSymbol()
        {
          Angle = 45,
          FontType = FontType.Type1,
          FontFamilyName = "Tahoma",
          FontEffects = FontEffects.Normal,
          HaloSize = 2.0,

          Symbol = new CIMPolygonSymbol
          {
            SymbolLayers = new CIMSymbolLayer[]
            {
                new CIMSolidFill
                {
                  Color = CIMColor.CreateRGBColor(0, 255, 0)
                }
            },
            UseRealWorldSymbolSizes = true
          }
        },
        MaxScale = 0,
        MinScale = 0,
        SymbolName = "TextSymbol-Green"
      },
      StandardLabelPlacementProperties = new CIMStandardLabelPlacementProperties
      {
        AllowOverlappingLabels = true,
        LineOffset = 1.0
      },
      MaplexLabelPlacementProperties = new CIMMaplexLabelPlacementProperties
      {
        AlignLabelToLineDirection = true,
        AvoidPolygonHoles = true
      }
    };

    // Blue label
    CIMLabelClass blueLabelClass = new CIMLabelClass
    {
      Name = "Blue",
      ExpressionTitle = "Expression-Blue",
      ExpressionEngine = LabelExpressionEngine.Arcade,
      Expression = "$feature.OBJECTID",
      ID = 2,
      Priority = 0,
      Visibility = true,
      TextSymbol = new CIMSymbolReference
      {
        Symbol = new CIMTextSymbol()
        {
          Angle = 45,
          FontType = FontType.Type1,
          FontFamilyName = "Consolas",
          FontEffects = FontEffects.Normal,
          HaloSize = 2.0,

          Symbol = new CIMPolygonSymbol
          {
            SymbolLayers = new CIMSymbolLayer[]
            {
                new CIMSolidFill
                {
                  Color = CIMColor.CreateRGBColor(0, 0, 255)
                }
            },
            UseRealWorldSymbolSizes = true
          }
        },
        MaxScale = 0,
        MinScale = 0,
        SymbolName = "TextSymbol-Blue"
      },
      StandardLabelPlacementProperties = new CIMStandardLabelPlacementProperties
      {
        AllowOverlappingLabels = true,
        LineOffset = 1.0
      },
      MaplexLabelPlacementProperties = new CIMMaplexLabelPlacementProperties
      {
        AlignLabelToLineDirection = true,
        AvoidPolygonHoles = true
      }
    };

    // Create a list of labels
    List<CIMLabelClass> labelClasses = new List<CIMLabelClass> { greenLabelClass, blueLabelClass };


    // Create linked feature description
    // Linked feature class name
    string linkedFeatureClassName = "WaterPipe";

    // Create fields for water pipe
    FieldDescription waterPipeGlobalID = FieldDescription.CreateGlobalIDField();
    FieldDescription pipeName = FieldDescription.CreateStringField("PipeName", 255);

    // Create a list of water pipe field descriptions
    List<FieldDescription> pipeFieldDescriptions = new List<FieldDescription> { waterPipeGlobalID, pipeName };

    // Create a linked feature class description
    FeatureClassDescription linkedFeatureClassDescription = new FeatureClassDescription(linkedFeatureClassName,
      pipeFieldDescriptions,
      new ShapeDescription(GeometryType.Polyline, spatialReference));

    // Create a SchemaBuilder object
    SchemaBuilder schemaBuilder = new SchemaBuilder(geodatabase);

    // Add the creation of the linked feature class to the list of DDL tasks
    FeatureClassToken linkedFeatureClassToken = schemaBuilder.Create(linkedFeatureClassDescription);

    // Create an annotation feature class description object to describe the feature class to create
    AnnotationFeatureClassDescription annotationFeatureClassDescription =
      new AnnotationFeatureClassDescription(annotationFeatureClassName, fieldDescriptions, shapeDescription,
        generalPlacementProperties, labelClasses, new FeatureClassDescription(linkedFeatureClassToken))
      {
        IsAutoCreate = true,
        IsSymbolIDRequired = false,
        IsUpdatedOnShapeChange = true
      };

    // Add the creation of the annotation feature class to the list of DDL tasks
    schemaBuilder.Create(annotationFeatureClassDescription);

    // Execute the DDL
    bool success = schemaBuilder.Build();

    // Inspect error messages
    if (!success)
    {
      IReadOnlyList<string> errorMessages = schemaBuilder.ErrorMessages;
      //etc.
    }
  }
}