Propagate IModel API changes across Python, JS, Rust SDKs and update C# docs

samples/cs/GettingStarted/src/AudioTranscriptionExample/Program.cs

@@ -23,10 +23,10 @@
 var catalog = await mgr.GetCatalogAsync();
 
 
-// Get a model using an alias and select the CPU model variant
+// Get a model using an alias and select the CPU variant
 var model = await catalog.GetModelAsync("whisper-tiny") ?? throw new System.Exception("Model not found");
-var modelVariant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.CPU);
-model.SelectVariant(modelVariant);
+var cpuVariant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.CPU);
+model.SelectVariant(cpuVariant);
 
 
 // Download the model (the method skips download if already cached)

samples/cs/GettingStarted/src/ModelManagementExample/Program.cs

@@ -67,26 +67,26 @@
 
 
 // OPTIONAL: `model` can be used directly and `model.SelectedVariant` will be used as the default.
-//           You can explicitly select or use a specific ModelVariant if you want more control
+//           You can explicitly select a specific variant if you want more control
 //           over the device and/or execution provider used.
-//           Model and ModelVariant can be used interchangeably in methods such as
+//           Model and its variants can be used interchangeably in methods such as
 //           DownloadAsync, LoadAsync, UnloadAsync and GetChatClientAsync.
 //
 // Choices:
-//   - Use a ModelVariant directly from the catalog if you know the variant Id
-//     - `var modelVariant = await catalog.GetModelVariantAsync("qwen2.5-0.5b-instruct-generic-gpu:3")`
+//   - Use a variant directly from the catalog if you know the variant Id
+//     - `var variant = await catalog.GetModelVariantAsync("qwen2.5-0.5b-instruct-generic-gpu:3")`
 //
-//   - Get the ModelVariant from Model.Variants
-//     - `var modelVariant = model.Variants.First(v => v.Id == "qwen2.5-0.5b-instruct-generic-cpu:4")`
-//     - `var modelVariant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.GPU)`
-//       - optional: update selected variant in `model` using `model.SelectVariant(modelVariant);` if you wish to use
+//   - Get the variant from Model.Variants
+//     - `var variant = model.Variants.First(v => v.Id == "qwen2.5-0.5b-instruct-generic-cpu:4")`
+//     - `var variant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.GPU)`
+//       - optional: update selected variant in `model` using `model.SelectVariant(variant);` if you wish to use
 //                   `model` in your code.
 
 // For this example we explicitly select the CPU variant, and call SelectVariant so all the following example code
 // uses the `model` instance.
 Console.WriteLine("Selecting CPU variant of model");
-var modelVariant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.CPU);
-model.SelectVariant(modelVariant);
+var cpuVariant = model.Variants.First(v => v.Info.Runtime?.DeviceType == DeviceType.CPU);
+model.SelectVariant(cpuVariant);
 
 
 // Download the model (the method skips download if already cached)

sdk/cs/README.md

@@ -9,7 +9,7 @@ The Foundry Local C# SDK provides a .NET interface for running AI models locally
 - **Chat completions** — synchronous and `IAsyncEnumerable` streaming via OpenAI-compatible types
 - **Audio transcription** — transcribe audio files with streaming support
 - **Download progress** — wire up an `Action<float>` callback for real-time download percentage
-- **Model variants** — select specific hardware/quantization variants per model alias
+- **Model variants** — select specific hardware/quantization variants per model alias via the IModel interface
 - **Optional web service** — start an OpenAI-compatible REST endpoint (`/v1/chat_completions`, `/v1/models`)
 - **WinML acceleration** — opt-in Windows hardware acceleration with automatic EP download
 - **Full async/await** — every operation supports `CancellationToken` and async patterns
@@ -138,11 +138,14 @@ var cached = await catalog.GetCachedModelsAsync();
 
 // List models currently loaded in memory
 var loaded = await catalog.GetLoadedModelsAsync();
+
+// Check for a newer version of a model
+var latest = await catalog.GetLatestVersionAsync(model);
 ```
 
 ### Model Lifecycle
 
-Each `Model` wraps one or more `ModelVariant` entries (different quantizations, hardware targets). The SDK auto-selects the best variant, or you can pick one:
+Each `Model` wraps one or more variant entries (different quantizations, hardware targets). The SDK auto-selects the best variant, or you can pick one:
 
 ```csharp
 // Check and select variants
@@ -293,8 +296,8 @@ Key types:
 | [`FoundryLocalManager`](./docs/api/microsoft.ai.foundry.local.foundrylocalmanager.md) | Singleton entry point — create, catalog, web service |
 | [`Configuration`](./docs/api/microsoft.ai.foundry.local.configuration.md) | Initialization settings |
 | [`ICatalog`](./docs/api/microsoft.ai.foundry.local.icatalog.md) | Model catalog interface |
-| [`Model`](./docs/api/microsoft.ai.foundry.local.model.md) | Model with variant selection |
-| [`ModelVariant`](./docs/api/microsoft.ai.foundry.local.modelvariant.md) | Specific model variant (hardware/quantization) |
+| [`IModel`](./docs/api/microsoft.ai.foundry.local.imodel.md) | Model interface — shared by Model and ModelVariant |
+| [`Model`](./docs/api/microsoft.ai.foundry.local.model.md) | Model with variant selection (implementation detail) |
 | [`OpenAIChatClient`](./docs/api/microsoft.ai.foundry.local.openaichatclient.md) | Chat completions (sync + streaming) |
 | [`OpenAIAudioClient`](./docs/api/microsoft.ai.foundry.local.openaiaudioclient.md) | Audio transcription (sync + streaming) |
 | [`ModelInfo`](./docs/api/microsoft.ai.foundry.local.modelinfo.md) | Full model metadata record |

sdk/cs/docs/api/microsoft.ai.foundry.local.icatalog.md

@@ -29,7 +29,7 @@ public abstract string Name { get; }
 List the available models in the catalog.
 
 ```csharp
-Task<List<Model>> ListModelsAsync(Nullable<CancellationToken> ct)
+Task<List<IModel>> ListModelsAsync(Nullable<CancellationToken> ct)
 ```
 
 #### Parameters
@@ -39,15 +39,15 @@ Optional CancellationToken.
 
 #### Returns
 
-[Task&lt;List&lt;Model&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
-List of Model instances.
+[Task&lt;List&lt;IModel&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+List of IModel instances.
 
 ### **GetModelAsync(String, Nullable&lt;CancellationToken&gt;)**
 
 Lookup a model by its alias.
 
 ```csharp
-Task<Model> GetModelAsync(string modelAlias, Nullable<CancellationToken> ct)
+Task<IModel> GetModelAsync(string modelAlias, Nullable<CancellationToken> ct)
 ```
 
 #### Parameters
@@ -60,15 +60,15 @@ Optional CancellationToken.
 
 #### Returns
 
-[Task&lt;Model&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
-The matching Model, or null if no model with the given alias exists.
+[Task&lt;IModel&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+The matching IModel, or null if no model with the given alias exists.
 
 ### **GetModelVariantAsync(String, Nullable&lt;CancellationToken&gt;)**
 
 Lookup a model variant by its unique model id.
 
 ```csharp
-Task<ModelVariant> GetModelVariantAsync(string modelId, Nullable<CancellationToken> ct)
+Task<IModel> GetModelVariantAsync(string modelId, Nullable<CancellationToken> ct)
 ```
 
 #### Parameters
@@ -81,15 +81,15 @@ Optional CancellationToken.
 
 #### Returns
 
-[Task&lt;ModelVariant&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
-The matching ModelVariant, or null if no variant with the given id exists.
+[Task&lt;IModel&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+The matching IModel, or null if no variant with the given id exists.
 
 ### **GetCachedModelsAsync(Nullable&lt;CancellationToken&gt;)**
 
 Get a list of currently downloaded models from the model cache.
 
 ```csharp
-Task<List<ModelVariant>> GetCachedModelsAsync(Nullable<CancellationToken> ct)
+Task<List<IModel>> GetCachedModelsAsync(Nullable<CancellationToken> ct)
 ```
 
 #### Parameters
@@ -99,15 +99,15 @@ Optional CancellationToken.
 
 #### Returns
 
-[Task&lt;List&lt;ModelVariant&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
-List of ModelVariant instances.
+[Task&lt;List&lt;IModel&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+List of IModel instances.
 
 ### **GetLoadedModelsAsync(Nullable&lt;CancellationToken&gt;)**
 
 Get a list of the currently loaded models.
 
 ```csharp
-Task<List<ModelVariant>> GetLoadedModelsAsync(Nullable<CancellationToken> ct)
+Task<List<IModel>> GetLoadedModelsAsync(Nullable<CancellationToken> ct)
 ```
 
 #### Parameters
@@ -117,5 +117,27 @@ Optional CancellationToken.
 
 #### Returns
 
-[Task&lt;List&lt;ModelVariant&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
-List of ModelVariant instances.
+[Task&lt;List&lt;IModel&gt;&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+List of IModel instances.
+
+### **GetLatestVersionAsync(IModel, Nullable&lt;CancellationToken&gt;)**
+
+Get the latest version of a model.
+This is used to check if a newer version of a model is available in the catalog for download.
+
+```csharp
+Task<IModel> GetLatestVersionAsync(IModel model, Nullable<CancellationToken> ct)
+```
+
+#### Parameters
+
+`model` [IModel](./microsoft.ai.foundry.local.imodel.md)<br>
+The model to check for the latest version.
+
+`ct` [Nullable&lt;CancellationToken&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.nullable-1)<br>
+Optional CancellationToken.
+
+#### Returns
+
+[Task&lt;IModel&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
+The latest version of the model. Will match the input if it is the latest version.

sdk/cs/docs/api/microsoft.ai.foundry.local.imodel.md

@@ -30,6 +30,42 @@ public abstract string Alias { get; }
 
 [String](https://docs.microsoft.com/en-us/dotnet/api/system.string)<br>
 
+### **Info**
+
+Full catalog metadata for this model or variant.
+
+```csharp
+public abstract ModelInfo Info { get; }
+```
+
+#### Property Value
+
+[ModelInfo](./microsoft.ai.foundry.local.modelinfo.md)<br>
+
+### **Variants**
+
+Variants of the model that are available. Variants are optimized for different devices.
+
+```csharp
+public abstract IReadOnlyList<IModel> Variants { get; }
+```
+
+#### Property Value
+
+[IReadOnlyList&lt;IModel&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.ireadonlylist-1)<br>
+
+### **SelectedVariant**
+
+Currently selected model variant in use.
+
+```csharp
+public abstract IModel SelectedVariant { get; }
+```
+
+#### Property Value
+
+[IModel](./microsoft.ai.foundry.local.imodel.md)<br>
+
 ## Methods
 
 ### **IsCachedAsync(Nullable&lt;CancellationToken&gt;)**
@@ -185,3 +221,16 @@ Optional cancellation token.
 
 [Task&lt;OpenAIAudioClient&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
 OpenAI.AudioClient
+
+### **SelectVariant(IModel)**
+
+Select a specific model variant from Variants to use for IModel operations.
+
+```csharp
+void SelectVariant(IModel variant)
+```
+
+#### Parameters
+
+`variant` [IModel](./microsoft.ai.foundry.local.imodel.md)<br>
+Model variant to select. Must be one of the variants in Variants.

sdk/cs/docs/api/microsoft.ai.foundry.local.model.md

@@ -15,22 +15,22 @@ Attributes [NullableContextAttribute](https://docs.microsoft.com/en-us/dotnet/ap
 ### **Variants**
 
 ```csharp
-public List<ModelVariant> Variants { get; internal set; }
+public IReadOnlyList<IModel> Variants { get; }
 ```
 
 #### Property Value
 
-[List&lt;ModelVariant&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1)<br>
+[IReadOnlyList&lt;IModel&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.ireadonlylist-1)<br>
 
 ### **SelectedVariant**
 
 ```csharp
-public ModelVariant SelectedVariant { get; internal set; }
+public IModel SelectedVariant { get; internal set; }
 ```
 
 #### Property Value
 
-[ModelVariant](./microsoft.ai.foundry.local.modelvariant.md)<br>
+[IModel](./microsoft.ai.foundry.local.imodel.md)<br>
 
 ### **Alias**
 
@@ -86,47 +86,24 @@ public Task<bool> IsLoadedAsync(Nullable<CancellationToken> ct)
 
 [Task&lt;Boolean&gt;](https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1)<br>
 
-### **SelectVariant(ModelVariant)**
+### **SelectVariant(IModel)**
 
 Select a specific model variant from [Model.Variants](./microsoft.ai.foundry.local.model.md#variants) to use for [IModel](./microsoft.ai.foundry.local.imodel.md) operations.
 
 ```csharp
-public void SelectVariant(ModelVariant variant)
+public void SelectVariant(IModel variant)
 ```
 
 #### Parameters
 
-`variant` [ModelVariant](./microsoft.ai.foundry.local.modelvariant.md)<br>
+`variant` [IModel](./microsoft.ai.foundry.local.imodel.md)<br>
 Model variant to select. Must be one of the variants in [Model.Variants](./microsoft.ai.foundry.local.model.md#variants).
 
 #### Exceptions
 
 [FoundryLocalException](./microsoft.ai.foundry.local.foundrylocalexception.md)<br>
 If variant is not valid for this model.
 
-### **GetLatestVersion(ModelVariant)**
-
-Get the latest version of the specified model variant.
-
-```csharp
-public ModelVariant GetLatestVersion(ModelVariant variant)
-```
-
-#### Parameters
-
-`variant` [ModelVariant](./microsoft.ai.foundry.local.modelvariant.md)<br>
-Model variant.
-
-#### Returns
-
-[ModelVariant](./microsoft.ai.foundry.local.modelvariant.md)<br>
-ModelVariant for latest version. Same as `variant` if that is the latest version.
-
-#### Exceptions
-
-[FoundryLocalException](./microsoft.ai.foundry.local.foundrylocalexception.md)<br>
-If variant is not valid for this model.
-
 ### **GetPathAsync(Nullable&lt;CancellationToken&gt;)**
 
 ```csharp

sdk/cs/docs/api/microsoft.ai.foundry.local.modelvariant.md

@@ -2,8 +2,10 @@
 
 Namespace: Microsoft.AI.Foundry.Local
 
+> **Note:** `ModelVariant` is an internal implementation detail. Use [`IModel`](./microsoft.ai.foundry.local.imodel.md) in public API code.
+
 ```csharp
-public class ModelVariant : IModel
+internal class ModelVariant : IModel
 ```
 
 Inheritance [Object](https://docs.microsoft.com/en-us/dotnet/api/system.object) → [ModelVariant](./microsoft.ai.foundry.local.modelvariant.md)<br>

sdk/js/README.md

@@ -217,9 +217,9 @@ The SDK is configured via `FoundryLocalConfig` when creating the manager:
 Auto-generated class documentation lives in [`docs/classes/`](docs/classes/):
 
 - [FoundryLocalManager](docs/classes/FoundryLocalManager.md) — SDK entry point, web service management
-- [Catalog](docs/classes/Catalog.md) — Model discovery and browsing
+- [Catalog](docs/classes/Catalog.md) — Model discovery, browsing, and latest version checking
 - [Model](docs/classes/Model.md) — High-level model with variant selection
-- [ModelVariant](docs/classes/ModelVariant.md) — Specific model variant: download, load, inference
+- [IModel](docs/interfaces/IModel.md) — Interface shared by Model and ModelVariant
 - [ChatClient](docs/classes/ChatClient.md) — Chat completions (sync and streaming)
 - [AudioClient](docs/classes/AudioClient.md) — Audio transcription (sync and streaming)
 - [ModelLoadManager](docs/classes/ModelLoadManager.md) — Low-level model loading management