Align WinML samples across SDKs

Add a C++ WinML verifier sample and expose the C++ EP discovery/download APIs needed for parity with the other SDK samples. Update the existing WinML sample paths and C++ sample build instructions.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: bmehta001

samples/README.md

@@ -12,3 +12,4 @@ Explore complete working examples that demonstrate how to use Foundry Local —
 | [**JavaScript**](js/) | 13 | Node.js SDK samples including native chat, embeddings, audio transcription, Electron desktop app, Copilot SDK integration, LangChain, tool calling, web server, and tutorials. |
 | [**Python**](python/) | 10 | Python samples using the OpenAI-compatible API, including chat, embeddings, audio transcription, LangChain integration, tool calling, web server, and tutorials. |
 | [**Rust**](rust/) | 9 | Rust SDK samples including native chat, embeddings, audio transcription, tool calling, web server, and tutorials. |
+| [**C++**](cpp/) | 2 | C++ SDK samples including WinML EP verification and live audio transcription. |

samples/cpp/live-audio-transcription/CMakeLists.txt

@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 3.20)
+
+project(LiveAudioTranscriptionSample LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+set(BUILD_TESTING OFF CACHE BOOL "Build C++ SDK tests" FORCE)
+add_subdirectory("${CMAKE_CURRENT_LIST_DIR}/../../../sdk/cpp" "${CMAKE_CURRENT_BINARY_DIR}/sdk-cpp")
+
+add_executable(LiveAudioTranscriptionSample main.cpp)
+target_compile_features(LiveAudioTranscriptionSample PRIVATE cxx_std_20)
+target_link_libraries(LiveAudioTranscriptionSample PRIVATE CppSdk)

samples/cpp/live-audio-transcription/README.md

@@ -9,20 +9,34 @@ available, falls back to synthetic PCM audio.
 
 ## Build
 
-```bash
-# With PortAudio (live microphone)
-g++ -std=c++20 -DHAS_PORTAUDIO main.cpp -lfoundry_local -lportaudio -o live-audio-transcription-example
+From this directory:
 
-# Without PortAudio (synthetic audio only)
-g++ -std=c++20 main.cpp -lfoundry_local -o live-audio-transcription-example
+```powershell
+cmake -S . -B out\build -G "Visual Studio 18 2026" -A x64 `
+  -DCMAKE_TOOLCHAIN_FILE="$env:VCPKG_ROOT\scripts\buildsystems\vcpkg.cmake" `
+  -DVCPKG_TARGET_TRIPLET=x64-windows-static-md
+
+cmake --build out\build --config Debug --target LiveAudioTranscriptionSample
 ```
 
+The C++ SDK loads `Microsoft.AI.Foundry.Local.Core.dll` from the executable
+directory. Copy the Foundry Local native binaries next to
+`LiveAudioTranscriptionSample.exe` before running the sample.
+
+The CMake project builds the synthetic-audio path by default. To use live
+microphone capture, add PortAudio to your build, define `HAS_PORTAUDIO`, and
+link PortAudio with `LiveAudioTranscriptionSample`.
+
+This sample requires a Foundry Local Core/catalog build that includes the live
+audio streaming model `nemotron-speech-streaming-en-0.6b`. If that model is not
+present in the catalog, the sample cannot run even though it builds successfully.
+
 ## Run
 
-```bash
-# Live microphone (requires PortAudio)
-./live-audio-transcription-example
+```powershell
+# Synthetic 440Hz sine wave
+.\out\build\Debug\LiveAudioTranscriptionSample.exe --synth
 
-# Synthetic 440Hz sine wave (no microphone needed)
-./live-audio-transcription-example --synth
+# Live microphone (requires a PortAudio-enabled build)
+.\out\build\Debug\LiveAudioTranscriptionSample.exe
 ```

samples/cpp/live-audio-transcription/main.cpp

@@ -19,6 +19,7 @@
 #include <iostream>
 #include <mutex>
 #include <string>
+#include <string_view>
 #include <thread>
 #include <vector>
 
@@ -32,6 +33,8 @@
 
 namespace {
 
+constexpr std::string_view kLiveAudioModelAlias = "nemotron-speech-streaming-en-0.6b";
+
 // Global flag for Ctrl+C graceful shutdown (mirrors JS process.on('SIGINT'))
 std::atomic<bool> g_running{true};
 
@@ -117,17 +120,19 @@ int main(int argc, char* argv[]) {
         std::cout << "===========================================================" << std::endl;
         std::cout << std::endl;
 
-        foundry_local::Configuration config;
-        config.appName = "foundry_local_samples";
+        foundry_local::Configuration config{"foundry_local_samples"};
 
         foundry_local::Manager::Create(config);
         auto& manager = foundry_local::Manager::Instance();
         manager.EnsureEpsDownloaded();
 
         auto& catalog = manager.GetCatalog();
-        auto* model = catalog.GetModel("nemotron-speech-streaming-en-0.6b");
+        auto* model = catalog.GetModel(kLiveAudioModelAlias);
         if (!model) {
-            throw std::runtime_error("Model \"nemotron-speech-streaming-en-0.6b\" not found in catalog");
+            throw std::runtime_error(
+                "Live audio model \"" + std::string(kLiveAudioModelAlias) +
+                "\" was not found in the catalog. Use a Foundry Local Core/catalog build "
+                "that includes live audio streaming support.");
         }
 
         std::cout << "Downloading model (if needed)..." << std::endl;
@@ -139,8 +144,6 @@ int main(int argc, char* argv[]) {
         model->Load();
         std::cout << "Model loaded" << std::endl;
 
-        // NOTE: CreateLiveTranscriptionSession() is not yet available in the C++ SDK.
-        // The audio client and session code below is forward-looking.
         foundry_local::OpenAIAudioClient audioClient(*model);
         auto session = audioClient.CreateLiveTranscriptionSession();
 

samples/cpp/verify-winml/CMakeLists.txt

@@ -0,0 +1,10 @@
+cmake_minimum_required(VERSION 3.20)
+
+project(VerifyWinMLCpp LANGUAGES CXX)
+
+set(BUILD_TESTING OFF CACHE BOOL "Build C++ SDK tests" FORCE)
+add_subdirectory("${CMAKE_CURRENT_LIST_DIR}/../../../sdk/cpp" "${CMAKE_CURRENT_BINARY_DIR}/sdk-cpp")
+
+add_executable(VerifyWinML main.cpp)
+target_compile_features(VerifyWinML PRIVATE cxx_std_17)
+target_link_libraries(VerifyWinML PRIVATE CppSdk)

samples/cpp/verify-winml/README.md

@@ -0,0 +1,41 @@
+# Verify WinML 2.0 Execution Providers (C++)
+
+This sample verifies that WinML 2.0 execution providers are correctly
+discovered, downloaded, and registered using the Foundry Local C++ SDK. It then
+uses registered WinML EP-backed model variants and finishes with one native
+streaming chat check.
+
+## Prerequisites
+
+- Windows with a compatible GPU or NPU
+- Windows App SDK 2.0 runtime installed
+- A Foundry Local WinML native runtime copied next to the sample executable
+
+The C++ SDK loads `Microsoft.AI.Foundry.Local.Core.dll` from the executable
+directory. Build or install a WinML-enabled SDK/runtime first, then copy the
+WinML native binaries next to `VerifyWinML.exe` before running the sample.
+
+## Build
+
+From this directory:
+
+```powershell
+cmake -S . -B out\build -G "Visual Studio 18 2026" -A x64 `
+  -DCMAKE_TOOLCHAIN_FILE="$env:VCPKG_ROOT\scripts\buildsystems\vcpkg.cmake" `
+  -DVCPKG_TARGET_TRIPLET=x64-windows-static-md
+
+cmake --build out\build --config Debug --target VerifyWinML
+```
+
+## Run
+
+```powershell
+.\out\build\Debug\VerifyWinML.exe
+```
+
+## What it tests
+
+1. **EP Discovery** - Lists all available execution providers.
+2. **EP Download & Registration** - Downloads and registers the available WinML EPs.
+3. **Model Catalog** - Lists text model variants backed by registered accelerated EPs.
+4. **Streaming Chat** - Runs streaming chat completion on a WinML EP-backed model via the native C++ SDK.