diff --git a/ErsatzTV/Controllers/Api/ApiResponseModels.cs b/ErsatzTV/Controllers/Api/ApiResponseModels.cs
new file mode 100644
index 000000000..c9ffedc1a
--- /dev/null
+++ b/ErsatzTV/Controllers/Api/ApiResponseModels.cs
@@ -0,0 +1,202 @@
+#nullable enable
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Domain.Scheduling;
+using ErsatzTV.Core.Scheduling;
+using ErsatzTV.FFmpeg.State;
+
+namespace ErsatzTV.Controllers.Api;
+
+// Flat collection response (no inheritance from MediaCardViewModel)
+public record CollectionApiResponse(
+    int Id,
+    string Name,
+    CollectionType CollectionType,
+    bool UseCustomPlaybackOrder,
+    MediaItemState State);
+
+// Flat smart collection response
+public record SmartCollectionApiResponse(
+    int Id,
+    string Name,
+    string Query);
+
+// Flat multi-collection response with inline items
+public record MultiCollectionApiResponse(
+    int Id,
+    string Name,
+    List<MultiCollectionItemApiResponse> Items,
+    List<MultiCollectionSmartItemApiResponse> SmartItems);
+
+public record MultiCollectionItemApiResponse(
+    int MultiCollectionId,
+    int CollectionId,
+    string CollectionName,
+    CollectionType CollectionType,
+    bool UseCustomPlaybackOrder,
+    MediaItemState State,
+    bool ScheduleAsGroup,
+    PlaybackOrder PlaybackOrder);
+
+public record MultiCollectionSmartItemApiResponse(
+    int MultiCollectionId,
+    int SmartCollectionId,
+    string SmartCollectionName,
+    string Query,
+    bool ScheduleAsGroup,
+    PlaybackOrder PlaybackOrder);
+
+// Flat media item response
+public record MediaItemApiResponse(
+    int MediaItemId,
+    string Name);
+
+// Block Item API Response - all data, flat structure
+public record BlockItemApiResponse(
+    int Id,
+    int Index,
+    CollectionType CollectionType,
+    CollectionApiResponse? Collection,
+    MultiCollectionApiResponse? MultiCollection,
+    SmartCollectionApiResponse? SmartCollection,
+    MediaItemApiResponse? MediaItem,
+    string? SearchTitle,
+    string? SearchQuery,
+    PlaybackOrder PlaybackOrder,
+    bool IncludeInProgramGuide,
+    bool DisableWatermarks,
+    List<WatermarkApiResponse> Watermarks,
+    List<GraphicsElementApiResponse> GraphicsElements);
+
+public record WatermarkApiResponse(
+    int Id,
+    string Name,
+    string? ImagePath,
+    ChannelWatermarkMode Mode,
+    ChannelWatermarkImageSource ImageSource,
+    WatermarkLocation Location,
+    WatermarkSize Size,
+    double Width,
+    double HorizontalMargin,
+    double VerticalMargin,
+    int FrequencyMinutes,
+    int DurationSeconds,
+    int Opacity,
+    bool PlaceWithinSourceContent,
+    string? OpacityExpression,
+    int ZIndex);
+
+public record GraphicsElementApiResponse(
+    int Id,
+    string Name,
+    string FileName);
+
+// Playlist Item API Response - all data, flat structure
+public record PlaylistItemApiResponse(
+    int Id,
+    int Index,
+    CollectionType CollectionType,
+    CollectionApiResponse? Collection,
+    MultiCollectionApiResponse? MultiCollection,
+    SmartCollectionApiResponse? SmartCollection,
+    MediaItemApiResponse? MediaItem,
+    PlaybackOrder PlaybackOrder,
+    int? Count,
+    bool PlayAll,
+    bool IncludeInProgramGuide);
+
+// Playlist response
+public record PlaylistApiResponse(
+    int Id,
+    int PlaylistGroupId,
+    string Name,
+    bool IsSystem);
+
+// Rerun collection response
+public record RerunCollectionApiResponse(
+    int Id,
+    string Name);
+
+// Filler preset response - flat
+public record FillerPresetApiResponse(
+    int Id,
+    string Name);
+
+// Schedule Item API Response - all data, flat structure
+public record ScheduleItemApiResponse(
+    int Id,
+    int Index,
+    StartType StartType,
+    TimeSpan? StartTime,
+    FixedStartTimeBehavior? FixedStartTimeBehavior,
+    PlayoutMode PlayoutMode,
+    CollectionType CollectionType,
+    CollectionApiResponse? Collection,
+    MultiCollectionApiResponse? MultiCollection,
+    SmartCollectionApiResponse? SmartCollection,
+    RerunCollectionApiResponse? RerunCollection,
+    PlaylistApiResponse? Playlist,
+    MediaItemApiResponse? MediaItem,
+    string? SearchTitle,
+    string? SearchQuery,
+    PlaybackOrder PlaybackOrder,
+    MarathonGroupBy MarathonGroupBy,
+    bool MarathonShuffleGroups,
+    bool MarathonShuffleItems,
+    int? MarathonBatchSize,
+    FillWithGroupMode FillWithGroupMode,
+    string? CustomTitle,
+    GuideMode GuideMode,
+    FillerPresetApiResponse? PreRollFiller,
+    FillerPresetApiResponse? MidRollFiller,
+    FillerPresetApiResponse? PostRollFiller,
+    FillerPresetApiResponse? TailFiller,
+    FillerPresetApiResponse? FallbackFiller,
+    List<WatermarkApiResponse> Watermarks,
+    List<GraphicsElementApiResponse> GraphicsElements,
+    string? PreferredAudioLanguageCode,
+    string? PreferredAudioTitle,
+    string? PreferredSubtitleLanguageCode,
+    ChannelSubtitleMode? SubtitleMode,
+    int? Count,
+    TimeSpan? PlayoutDuration);
+
+// Paged response types
+public record PagedCollectionsApiResponse(int TotalCount, List<CollectionApiResponse> Page);
+
+// Deco API Response - all data, flat structure
+public record DecoApiResponse(
+    int Id,
+    int DecoGroupId,
+    string DecoGroupName,
+    string Name,
+    DecoMode WatermarkMode,
+    List<WatermarkApiResponse> Watermarks,
+    bool UseWatermarkDuringFiller,
+    DecoMode GraphicsElementsMode,
+    List<GraphicsElementApiResponse> GraphicsElements,
+    bool UseGraphicsElementsDuringFiller,
+    DecoMode BreakContentMode,
+    List<DecoBreakContentApiResponse> BreakContent,
+    DecoMode DefaultFillerMode,
+    CollectionType DefaultFillerCollectionType,
+    CollectionApiResponse? DefaultFillerCollection,
+    MediaItemApiResponse? DefaultFillerMediaItem,
+    MultiCollectionApiResponse? DefaultFillerMultiCollection,
+    SmartCollectionApiResponse? DefaultFillerSmartCollection,
+    bool DefaultFillerTrimToFit,
+    DecoMode DeadAirFallbackMode,
+    CollectionType DeadAirFallbackCollectionType,
+    CollectionApiResponse? DeadAirFallbackCollection,
+    MediaItemApiResponse? DeadAirFallbackMediaItem,
+    MultiCollectionApiResponse? DeadAirFallbackMultiCollection,
+    SmartCollectionApiResponse? DeadAirFallbackSmartCollection);
+
+public record DecoBreakContentApiResponse(
+    int Id,
+    CollectionType CollectionType,
+    CollectionApiResponse? Collection,
+    MediaItemApiResponse? MediaItem,
+    MultiCollectionApiResponse? MultiCollection,
+    SmartCollectionApiResponse? SmartCollection,
+    PlaylistApiResponse? Playlist,
+    DecoBreakPlacement Placement);