Building AI Apps with the Foundry Local C# SDK
What Is Foundry Local? Foundry Local is a lightweight runtime designed to run AI models directly on user devices. It supports a wide range of hardware (CPU, GPU, NPU) and provides a consistent developer experience across platforms. The SDKs are available in multiple languages, including Python, JavaScript, Rust, and now C#. Why a C# SDK? The C# SDK brings Foundry Local into the heart of the .NET ecosystem. It allows developers to: Download and manage models locally. Run inference using OpenAI-compatible APIs. Integrate seamlessly with existing .NET applications. This means you can build intelligent apps that run offline, reduce latency, and maintain data privacy—all without sacrificing developer productivity. Bootstrap Process: How the SDK Gets You Started One of the most developer-friendly aspects of the C# SDK is its automatic bootstrap process. Here's what happens under the hood when you initialise the SDK: Service Discovery and Startup The SDK automatically locates the Foundry Local installation on the device and starts the inference service if it's not already running. Model Download and Caching If the specified model isn't already cached locally, the SDK will download the most performant model variant (e.g. GPU, CPU, NPU) for the end user's hardware from the Foundry model catalog. This ensures you're always working with the latest optimised version. Model Loading into Inference Service Once downloaded (or retrieved from cache), the model is loaded into the Foundry Local inference engine, ready to serve requests. This streamlined process means developers can go from zero to inference with just a few lines of code—no manual setup or configuration required. Leverage Your Existing AI Stack One of the most exciting aspects of the Foundry Local C# SDK is its compatibility with popular AI tools such as: OpenAI SDK - Foundry local provides an OpenAI compliant chat completions (and embedding) API meaning. If you’re already using `OpenAI` chat completions API, you can reuse your existing code with minimal changes. Semantic Kernel - Foundry Local also integrates well with Semantic Kernel, Microsoft’s open-source framework for building AI agents. You can use Foundry Local models as plugins or endpoints within Semantic Kernel workflows—enabling advanced capabilities like memory, planning, and tool calling. Quick Start Example Follow these three steps: 1. Create a new project Create a new C# project and navigate to it: dotnet new console -n hello-foundry-local cd hello-foundry-local 2. Install NuGet packages Install the following NuGet packages into your project: dotnet add package Microsoft.AI.Foundry.Local --version 0.1.0 dotnet add package OpenAI --version 2.2.0-beta.4 3. Use the OpenAI SDK with Foundry Local The following example demonstrates how to use the OpenAI SDK with Foundry Local. The code initializes the Foundry Local service, loads a model, and generates a response using the OpenAI SDK. Copy-and-paste the following code into a C# file named Program.cs: using Microsoft.AI.Foundry.Local; using OpenAI; using OpenAI.Chat; using System.ClientModel; using System.Diagnostics.Metrics; var alias = "phi-3.5-mini"; var manager = await FoundryLocalManager.StartModelAsync(aliasOrModelId: alias); var model = await manager.GetModelInfoAsync(aliasOrModelId: alias); ApiKeyCredential key = new ApiKeyCredential(manager.ApiKey); OpenAIClient client = new OpenAIClient(key, new OpenAIClientOptions { Endpoint = manager.Endpoint }); var chatClient = client.GetChatClient(model?.ModelId); var completionUpdates = chatClient.CompleteChatStreaming("Why is the sky blue'"); Console.Write($"[ASSISTANT]: "); foreach (var completionUpdate in completionUpdates) { if (completionUpdate.ContentUpdate.Count > 0) { Console.Write(completionUpdate.ContentUpdate[0].Text); } } Run the code using the following command: dotnet run Final thoughts The Foundry Local C# SDK empowers developers to build intelligent, privacy-preserving applications that run anywhere. Whether you're working on desktop, mobile, or embedded systems, this SDK offers a robust and flexible way to bring AI closer to your users. Ready to get started? Dive into the official documentation: Getting started guide C# Reference documentation You can also make contributions to the C# SDK by creating a PR on GitHub: Foundry Local on GitHubThe Future of AI: Evaluating and optimizing custom RAG agents using Azure AI Foundry
This blog post explores best practices for evaluating and optimizing Retrieval-Augmented Generation (RAG) agents using Azure AI Foundry. It introduces the RAG triad metrics—Retrieval, Groundedness, and Relevance—and demonstrates how to apply them using Azure AI Search and agentic retrieval for custom agents. Readers will learn how to fine-tune search parameters, use end-to-end evaluation metrics and golden retrieval metrics like XDCG and Max Relevance, and leverage Azure AI Foundry tools to build trustworthy, high-performing AI agents.Announcing Live Interpreter API - Now in Public Preview
Today, we’re excited to introduce Live Interpreter –a breakthrough new capability in Azure Speech Translation – that makes real-time, multilingual communication effortless. Live Interpreter continuously identifies the language being spoken without requiring you to set an input language and delivers low latency speech-to-speech translation in a natural voice that preserves the speaker’s style and tone.
Building Enterprise Voice-Enabled AI Agents with Azure Voice Live API
The sample application covered in this post demonstrates two approaches in an end-to-end solution that includes product search, order management, automated shipment creation, intelligent analytics, and comprehensive business intelligence through Microsoft Fabric integration. Use Case Scenario: Retail Fashion Agent Core Business Capabilities: Product Discovery and Ordering: Natural language product search across fashion categories (Winter wear, Active wear, etc.) and order placement. REST APIs hosted in Azure Function Apps provide this functionality and a Swagger definition is configured in the Application for tool action. Automated Fulfillment: Integration with Azure Logic Apps for shipment creation in Azure SQL Database Policy Support: Vector-powered QnA for returns, payment issues, and customer policies. Azure AI Search & File Search capabilities are used for this requirement. Conversation Analytics: AI-powered analysis using GPT-4o for sentiment scoring and performance evaluation. The Application captures the entire conversation between the customer and Agent and sends them to an Agent running in Azure Logic Apps to perform call quality assessment, before storing the results in Azure CosmosDB. When during the voice call the customer indicates that the conversation can be concluded, the Agent autonomously sends the conversation history to the Azure Logic App to perform quality assessment. Advanced Analytics Pipeline: Real-time Data Mirroring: Automatic synchronization from Azure Cosmos DB to Microsoft Fabric OneLake Business Intelligence: Custom Data Agents in Fabric for trend analysis and insights Executive Dashboards: Power BI reports for comprehensive performance monitoring Technical Architecture Overview The solution presents two approaches, each optimized for different enterprise scenarios: 🎯Approach 1: Direct Model Integration with GPT-Realtime Architecture Components This approach provides direct integration with Azure Voice Live API using GPT-Realtime model for immediate speech-to-speech conversational experiences without intermediate text processing. The Application connects to the Voice Live API uses a Web socket connection. The semantics of this API are similar to the one used when connecting to the GPT-Realtime API directly. The Voice Live API provides additional configurability, like the choice of a custom Voice from Azure Speech Services, options for echo cancellation, noise reduction and plugging an Avatar integration. Core Technical Stack: GPT-Realtime Model: Direct audio-to-audio processing Azure Speech Voice: High-quality TTS synthesis (en-IN-AartiIndicNeural) WebSocket Communication: Real-time bidirectional audio streaming Voice Activity Detection: Server-side VAD for natural conversation flow Client-Side Function Calling: Full control over tool execution logic Key Session Configuration The Direct Model Integration uses the session configuration below: session_config = { "input_audio_sampling_rate": 24000, "instructions": system_instructions, "turn_detection": { "type": "server_vad", "threshold": 0.5, "prefix_padding_ms": 300, "silence_duration_ms": 500, }, "tools": tools_list, "tool_choice": "auto", "input_audio_noise_reduction": {"type": "azure_deep_noise_suppression"}, "input_audio_echo_cancellation": {"type": "server_echo_cancellation"}, "voice": { "name": "en-IN-AartiIndicNeural", "type": "azure-standard", "temperature": 0.8, }, "input_audio_transcription": {"model": "whisper-1"}, } Configuration Highlights: 24kHz Audio Sampling: High-quality audio processing for natural speech Server VAD: Optimized threshold (0.5) with 300ms padding for natural conversation flow Azure Deep Noise Suppression: Advanced noise reduction for clear audio Indic Voice Support: en-IN-AartiIndicNeural for localized customer experience Whisper-1 Transcription: Accurate speech recognition for conversation logging Connecting to the Azure Voice Live API The voicelive_modelclient.py demonstrates advanced WebSocket handling for real-time audio streaming: def get_websocket_url(self, access_token: str) -> str: """Generate WebSocket URL for Voice Live API.""" azure_ws_endpoint = endpoint.rstrip("/").replace("https://", "wss://") return ( f"{azure_ws_endpoint}/voice-live/realtime?api-version={api_version}" f"&model={model_name}" f"&agent-access-token={access_token}" ) async def connect(self): if self.is_connected(): # raise Exception("Already connected") self.log("Already connected") # Get access token access_token = self.get_azure_token() # Build WebSocket URL and headers ws_url = self.get_websocket_url(access_token) self.ws = await websockets.connect( ws_url, additional_headers={ "Authorization": f"Bearer {self.get_azure_token()}", "x-ms-client-request-id": str(uuid.uuid4()), }, ) print(f"Connected to Azure Voice Live API....") asyncio.create_task(self.receive()) await self.update_session() Function Calling Implementation The Direct Model Integration provides client-side function execution with complete control: tools_list = [ { "type": "function", "name": "perform_search_based_qna", "description": "call this function to respond to the user query on Contoso retail policies, procedures and general QnA", "parameters": { "type": "object", "properties": {"query": {"type": "string"}}, "required": ["query"], }, }, { "type": "function", "name": "create_delivery_order", "description": "call this function to create a delivery order based on order id and destination location", "parameters": { "type": "object", "properties": { "order_id": {"type": "string"}, "destination": {"type": "string"}, }, "required": ["order_id", "destination"], }, }, { "type": "function", "name": "perform_call_log_analysis", "description": "call this function to analyze call log based on input call log conversation text", "parameters": { "type": "object", "properties": { "call_log": {"type": "string"}, }, "required": ["call_log"], }, }, { "type": "function", "name": "search_products_by_category", "description": "call this function to search for products by category", "parameters": { "type": "object", "properties": { "category": {"type": "string"}, }, "required": ["category"], }, }, { "type": "function", "name": "order_products", "description": "call this function to order products by product id and quantity", "parameters": { "type": "object", "properties": { "product_id": {"type": "string"}, "quantity": {"type": "integer"}, }, "required": ["product_id", "quantity"], }, } ] 🤖 Approach 2: Azure AI Foundry Agent Integration Architecture Components This approach leverages existing Azure AI Foundry Service Agents, providing enterprise-grade voice capabilities as a clean wrapper over pre-configured agents. It does not entail any code changes to the Agent itself to voice enable it. Core Technical Stack: Azure Fast Transcript: Advanced multi-language speech-to-text processing Azure AI Foundry Agent: Pre-configured Agent with autonomous capabilities GPT-4o-mini Model: Agent-configured model for text processing Neural Voice Synthesis: Indic language optimized TTS Semantic VAD: Azure semantic voice activity detection Session Configuration The Agent Integration approach uses advanced semantic voice activity detection: session_config = { "input_audio_sampling_rate": 24000, "turn_detection": { "type": "azure_semantic_vad", "threshold": 0.3, "prefix_padding_ms": 200, "silence_duration_ms": 200, "remove_filler_words": False, "end_of_utterance_detection": { "model": "semantic_detection_v1", "threshold": 0.01, "timeout": 2, }, }, "input_audio_noise_reduction": {"type": "azure_deep_noise_suppression"}, "input_audio_echo_cancellation": {"type": "server_echo_cancellation"}, "voice": { "name": "en-IN-AartiIndicNeural", "type": "azure-standard", "temperature": 0.8, }, "input_audio_transcription": {"model": "azure-speech", "language": "en-IN, hi-IN"}, } Key Differentiators: Semantic VAD: Intelligent voice activity detection with utterance prediction Multi-language Support: Azure Speech with en-IN and hi-IN language support End-of-Utterance Detection: AI-powered conversation turn management Filler Word Handling: Configurable processing of conversational fillers Agent Integration Code The voicelive_client.py demonstrates seamless integration with Azure AI Foundry Agents. Notice that we need to provide the Azure AI Foundry Project Name and an ID of the Agent in it. We do not need to pass the model's name here, since the Agent is already configured with one. def get_websocket_url(self, access_token: str) -> str: """Generate WebSocket URL for Voice Live API.""" azure_ws_endpoint = endpoint.rstrip("/").replace("https://", "wss://") return ( f"{azure_ws_endpoint}/voice-live/realtime?api-version={api_version}" f"&agent-project-name={project_name}&agent-id={agent_id}" f"&agent-access-token={access_token}" ) async def connect(self): """Connects the client using a WS Connection to the Realtime API.""" if self.is_connected(): # raise Exception("Already connected") self.log("Already connected") # Get access token access_token = self.get_azure_token() # Build WebSocket URL and headers ws_url = self.get_websocket_url(access_token) self.ws = await websockets.connect( ws_url, additional_headers={ "Authorization": f"Bearer {self.get_azure_token()}", "x-ms-client-request-id": str(uuid.uuid4()), }, ) print(f"Connected to Azure Voice Live API....") asyncio.create_task(self.receive()) await self.update_session() Advanced Analytics Pipeline GPT-4o Powered Call Analysis The solution implements conversation analytics using Azure Logic Apps with GPT-4o: { "functions": [ { "name": "evaluate_call_log", "description": "Evaluate call log for Contoso Retail customer service call", "parameters": { "properties": { "call_reason": { "description": "Categorized call reason from 50+ predefined scenarios", "type": "string" }, "customer_satisfaction": { "description": "Overall satisfaction assessment", "type": "string" }, "customer_sentiment": { "description": "Emotional tone analysis", "type": "string" }, "call_rating": { "description": "Numerical rating (1-5 scale)", "type": "number" }, "call_rating_justification": { "description": "Detailed reasoning for rating", "type": "string" } } } } ] } Microsoft Fabric Integration The analytics pipeline extends into Microsoft Fabric for enterprise business intelligence: Fabric Integration Features: Real-time Data Mirroring: Cosmos DB to OneLake synchronization Custom Data Agents: Business-specific analytics agents in Fabric Copilot Integration: Natural language business intelligence queries Power BI Dashboards: Interactive reports and executive summaries Artefacts for reference The source code of the solution is available in the GitHub Repo here. An article on this topic is published on LinkedIn here A video recording of the demonstration of this App is available below: Part1 - walkthrough of the Agent configuration in Azure AI Foundry - here Part2 - demonstration of the Application that integrates with the Azure Voice Live API - here Part 3 - demonstration of the Microsoft Fabric Integration, Data Agents, Copilot in Fabric and Power BI for insights and analysis - here Conclusion Azure Voice Live API enables enterprises to build sophisticated voice-enabled AI assistants using two distinct architectural approaches. The Direct Model Integration provides ultra-low latency for real-time applications, while the Azure AI Foundry Agent Integration offers enterprise-grade governance and autonomous operation. Both approaches deliver the same comprehensive business capabilities: Natural voice interactions with advanced VAD and noise suppression Complete retail workflow automation from inquiry to fulfillment AI-powered conversation analytics with sentiment scoring Enterprise business intelligence through Microsoft Fabric integration The choice between approaches depends on your specific requirements: Choose Direct Model Integration for custom function calling and minimal latency Choose Azure AI Foundry Agent Integration for enterprise governance and existing investmentsThe Future of AI: Optimize Your Site for Agents - It's Cool to be a Tool
Learn how to optimize your website for AI agents like Manus using NLWeb, MCP, structured data, and agent-responsive design. Discover best practices to improve discoverability, usability, and natural language access for autonomous assistants in the evolving agentic web.
Build Custom Engine Agents in AI Foundry for Microsoft 365 Copilot
If you already have a multi‑agent AI application, you can surface it inside Microsoft 365 Copilot without adding another orchestration layer. Use a thin “proxy agent” built with the Microsoft 365 Agents SDK to handle Copilot activities and forward a simple request to your existing backend (in this example, we will use a simple Semantic Kernel multi‑agent workflow on top of Azure AI Foundry that writes and SEO‑optimizes blog posts). Develop fast and deploy to Azure with the Microsoft 365 Agents Toolkit for VS Code.Announcing a new Azure AI Translator API (Public Preview)
Microsoft has launched the Azure AI Translator API (Public Preview), offering flexible translation options using either neural machine translation (NMT) or generative AI models like GPT-4o. The API supports tone, gender, and adaptive custom translation, allowing enterprises to tailor output for real-time or human-reviewed workflows. Customers can mix models in a single request and authenticate via resource key or Entra ID. LLM features require deployment in Azure AI Foundry. Pricing is based on characters (NMT) or tokens (LLMs).The Future of AI: Vibe Code with Adaptive Custom Translation
This blog explores how vibe coding—a conversational, flow-based development approach—was used to build the AdaptCT playground in Azure AI Foundry. It walks through setting up a productive coding environment with GitHub Copilot in Visual Studio Code, configuring the Copilot agent, and building a translation playground using Adaptive Custom Translation (AdaptCT). The post includes real-world code examples, architectural insights, and advanced UI patterns. It also highlights how AdaptCT fine-tunes LLM outputs using domain-specific reference sentence pairs, enabling more accurate and context-aware translations. The blog concludes with best practices for vibe coding teams and a forward-looking view of AI-augmented development paradigms.
Unveiling the Next Generation of Table Structure Recognition
In an era where data is abundant, the ability to accurately and efficiently extract structured information like tables from diverse document types is critical. For instance, consider the complexities of a balance sheet with multiple types of assets or an invoice with various charges, both presented in a table format that can be challenging even for humans to interpret. Traditional parsing methods often struggle with the complexity and variability of real-world tables, leading to manual intervention and inefficient workflows. This is because these methods typically rely on rigid rules or predefined templates that fail when encountering variations in layout, formatting, or content, which are common in real-world documents. While the promise of Generative AI and Large Language Models (LLMs) in document understanding is vast, our research in table parsing has revealed a critical insight: for tasks requiring precision in data alignment, such as correctly associating data cells with their respective row and column headers, classical computer vision techniques currently offer superior performance. Generative AI models, despite their powerful contextual understanding, can sometimes exhibit inconsistencies and misalignments in tabular structures, leading to compromised data integrity (Figure 1). Therefore, Azure Document Intelligence (DI) and Content Understanding (CU) leverages an even more robust and proven computer vision algorithms to ensure the foundational accuracy and consistency that enterprises demand. Figure 1: Vision LLMs struggle to accurately recognize table structure, even in simple tables. Our current table recognizer excels at accurately identifying table structures, even those with complex layouts, rotations, or curved shapes. However, it does have its limitations. For example, it occasionally fails to properly delineate a table where the logical boundaries are not visible but must be inferred from the larger document context, making suboptimal inferences. Furthermore, its architectural design makes it challenging to accelerate on modern GPU platforms, impacting its runtime efficiency. Taking these limitations in considerations and building upon our existing foundation, we are introducing the latest advancement in our table structure recognizer. This new version significantly enhances both performance and accuracy, addressing key challenges in document processing. Precise Separation Line Placement We've made significant strides in the precision of separation line placement. While predicting these separation lines might seem deceptively simple, it comes with subtle yet significant challenges. In many real-world documents, these are logical separation lines, meaning they are not always visibly drawn on the page. Instead, their positions are often implied by an array of nuanced visual cues such as table headers/footers, dot filler text, background color changes, and even the spacing and alignment of content within the cells. Figure 2: Visual Comparison of separation line prediction of current and the new version We've developed a novel model architecture that can be trained end-to-end to directly tackle the above challenges. Recognizing the difficulty for humans to consistently label table separation lines, we've devised a training objective that combines Hungarian matching with an adaptive matching weight to correctly align predictions with ground truth even when the latter is noisy. Additionally, we've incorporated a loss function inspired by speech recognition to encourage the model to accurately predict the correct number of separation lines, further enhancing its performance. Our improved algorithms now respect visual cues more effectively, ensuring that separation lines are placed precisely where they belong. This leads to cleaner, more accurate table structures and ultimately, more reliable data extraction. Figure 2 shows the comparison between the current model and the new model on a few examples. Some quantitative results can be found in Table 1. TSR (current, in %) TSR-v2 (next-gen, in %) Segment Precision Recall F1-Score Precision Recall F1-score Latin 90.2 90.7 90.4 94.0 95.7 94.8 Chinese 96.1 95.3 95.7 97.3 96.8 97.0 Japanese 93.5 93.8 93.7 95.1 97.1 96.1 Korean 95.3 95.9 95.6 97.5 97.8 97.7 Table 1: Table structure accuracy measured by cell prediction precision and recall rates at IoU (intersection over union) threshold of 0.5. Tested on in-house test datasets covering four different scripts. A Data-Driven, GPU-Accelerated Design Another innovation in this release is its data-driven, fully GPU-accelerated design. This architectural shift delivers enhanced quality and significantly faster inference speeds, which is critical for processing large volumes of documents. The design carefully considers the trade-off between model capability and latency requirements, prioritizing an architecture that leverages the inherent parallelism of GPUs. This involves favoring highly parallelizable models over serial approaches to maximize GPU utilization. Furthermore, post-processing logic has been minimized to prevent it from becoming a bottleneck. This comprehensive approach has resulted in a drastic reduction in processing latency, from 250ms per image to less than 10ms. Fueling Robustness with Synthetic Data Achieving the high level of accuracy and robustness required for enterprise-grade table recognition demands vast quantities of high-quality training data. To meet this need efficiently, we've strategically incorporated synthetic data into our development pipeline. A few examples can be found in Figure 3. Figure 3: Synthesized tables Synthetic data offers significant advantages: it's cost-effective to generate and provides unparalleled control over the dataset. This allows us to rapidly synthesize diverse and specific table styles, including rare or challenging layouts, which would be difficult and expensive to collect from real-world documents. Crucially, synthetic data comes with perfectly consistent labels. Unlike human annotation, which can introduce variability, synthetic data ensures that our models learn from a flawlessly labeled ground truth, leading to more reliable and precise training outcomes. Summary This latest version of our table structure recognizer enhances critical document understanding capabilities. We've refined separation line placement to better respect visual cues and implied structures, supported by our synthetic data approach for consistent training. This enhancement, in turn, allows users to maintain the table structure as intended, reducing the need for manual post-processing to clean up the structured output. Additionally, a GPU-accelerated, data-driven design delivers both improved quality and faster performance, crucial for processing large document volumes.Announcing gpt-realtime on Azure AI Foundry:
We are thrilled to announce that we are releasing today the general availability of our latest advancement in speech-to-speech technology: gpt-realtime. This new model represents a significant leap forward in our commitment to providing advanced and reliable speech-to-speech solutions. gpt-realtime is a new S2S (speech-to-speech) model with improved instruction following, designed to merge all of our speech-to-speech improvements into a single, cohesive model. This model is now available in the Real-time API, offering enhanced voice naturalness, higher audio quality, and improved function calling capabilities. Key Features New, natural, expressive voices: New voice options (Marin and Cedar) that bring a new level of naturalness and clarity to speech synthesis. Improved Instruction Following: Enhanced capabilities to follow instructions more accurately and reliably. Enhanced Voice Naturalness: More lifelike and expressive voice output. Higher Audio Quality: Superior audio quality for a better user experience. Improved Function Calling: Enhanced ability to call custom code defined by developers. Image Input Support: Add images to context and discuss them via voice—no video required. Check out the model card here: gpt-realtime Pricing Pricing for gpt-realtime is 20% lower compared to the previous gpt-4o-realtime preview: Pricing is based on usage per 1 million tokens. Below is the breakdown: Getting Started gpt-realtime is available on Azure AI Foundry via Azure Models direct from Azure today. We are excited to see how developers and users will leverage these new capabilities to create innovative and impactful solutions. Check out the model on Azure AI Foundry and see detailed documentation in Microsoft Learn docs.
