stream

client . Runs . CreateRunStreamingAsync ( thread . Id , agent . Id ) ; await foreach ( StreamingUpdate update in stream ) { if ( update . UpdateKind == StreamingUpdateReason . RunCreated ) { Console . WriteLine ( "--- Run started! ---" ) ; } else if ( update is MessageContentUpdate contentUpdate ) { Console . Write ( contentUpdate . Text ) ; } else if ( update . UpdateKind == StreamingUpdateReason . RunCompleted ) { Console . WriteLine ( "\n--- Run completed! ---" ) ; } } 5. Function Calling // Define function tool FunctionToolDefinition weatherTool = new ( name : "getCurrentWeather" , description : "Gets the current weather at a location." , parameters : BinaryData . FromObjectAsJson ( new { Type = "object" , Properties = new { Location = new { Type = "string" , Description = "City and state, e.g. San Francisco, CA" } , Unit = new { Type = "string" , Enum = new [ ] { "c" , "f" } } } , Required = new [ ] { "location" } } , new JsonSerializerOptions { PropertyNamingPolicy = JsonNamingPolicy . CamelCase } ) ) ; // Create agent with function PersistentAgent agent = await client . Administration . CreateAgentAsync ( model : modelDeploymentName , name : "Weather Bot" , instructions : "You are a weather bot." , tools : [ weatherTool ] ) ; // Handle function calls during polling do { await Task . Delay ( 500 ) ; run = await client . Runs . GetRunAsync ( thread . Id , run . Id ) ; if ( run . Status == RunStatus . RequiresAction && run . RequiredAction is SubmitToolOutputsAction submitAction ) { List < ToolOutput

outputs

[ ] ; foreach ( RequiredToolCall toolCall in submitAction . ToolCalls ) { if ( toolCall is RequiredFunctionToolCall funcCall ) { // Execute function and get result string result = ExecuteFunction ( funcCall . Name , funcCall . Arguments ) ; outputs . Add ( new ToolOutput ( toolCall , result ) ) ; } } run = await client . Runs . SubmitToolOutputsToRunAsync ( run , outputs , toolApprovals : null ) ; } } while ( run . Status == RunStatus . Queued || run . Status == RunStatus . InProgress ) ; 6. File Search with Vector Store // Upload file PersistentAgentFileInfo file = await client . Files . UploadFileAsync ( filePath : "document.txt" , purpose : PersistentAgentFilePurpose . Agents ) ; // Create vector store PersistentAgentsVectorStore vectorStore = await client . VectorStores . CreateVectorStoreAsync ( fileIds : [ file . Id ] , name : "my_vector_store" ) ; // Create file search resource FileSearchToolResource fileSearchResource = new ( ) ; fileSearchResource . VectorStoreIds . Add ( vectorStore . Id ) ; // Create agent with file search PersistentAgent agent = await client . Administration . CreateAgentAsync ( model : modelDeploymentName , name : "Document Assistant" , instructions : "You help users find information in documents." , tools : [ new FileSearchToolDefinition ( ) ] , toolResources : new ToolResources { FileSearch = fileSearchResource } ) ; 7. Bing Grounding var bingConnectionId = Environment . GetEnvironmentVariable ( "AZURE_BING_CONNECTION_ID" ) ; BingGroundingToolDefinition bingTool = new ( new BingGroundingSearchToolParameters ( [ new BingGroundingSearchConfiguration ( bingConnectionId ) ] ) ) ; PersistentAgent agent = await client . Administration . CreateAgentAsync ( model : modelDeploymentName , name : "Search Agent" , instructions : "Use Bing to answer questions about current events." , tools : [ bingTool ] ) ; 8. Azure AI Search AzureAISearchToolResource searchResource = new ( connectionId : searchConnectionId , indexName : "my_index" , topK : 5 , filter : "category eq 'documentation'" , queryType : AzureAISearchQueryType . Simple ) ; PersistentAgent agent = await client . Administration . CreateAgentAsync ( model : modelDeploymentName , name : "Search Agent" , instructions : "Search the documentation index to answer questions." , tools : [ new AzureAISearchToolDefinition ( ) ] , toolResources : new ToolResources { AzureAISearch = searchResource } ) ; 9. Cleanup await client . Threads . DeleteThreadAsync ( thread . Id ) ; await client . Administration . DeleteAgentAsync ( agent . Id ) ; await client . VectorStores . DeleteVectorStoreAsync ( vectorStore . Id ) ; await client . Files . DeleteFileAsync ( file . Id ) ; Available Tools Tool Class Purpose Code Interpreter CodeInterpreterToolDefinition Execute Python code, generate visualizations File Search FileSearchToolDefinition Search uploaded files via vector stores Function Calling FunctionToolDefinition Call custom functions Bing Grounding BingGroundingToolDefinition Web search via Bing Azure AI Search AzureAISearchToolDefinition Search Azure AI Search indexes OpenAPI OpenApiToolDefinition Call external APIs via OpenAPI spec Azure Functions AzureFunctionToolDefinition Invoke Azure Functions MCP MCPToolDefinition Model Context Protocol tools SharePoint SharepointToolDefinition Access SharePoint content Microsoft Fabric MicrosoftFabricToolDefinition Access Fabric data Streaming Update Types Update Type Description StreamingUpdateReason.RunCreated Run started StreamingUpdateReason.RunInProgress Run processing StreamingUpdateReason.RunCompleted Run finished StreamingUpdateReason.RunFailed Run errored MessageContentUpdate Text content chunk RunStepUpdate Step status change Key Types Reference Type Purpose PersistentAgentsClient Main entry point PersistentAgent Agent with model, instructions, tools PersistentAgentThread Conversation thread PersistentThreadMessage Message in thread ThreadRun Execution of agent against thread RunStatus Queued, InProgress, RequiresAction, Completed, Failed ToolResources Combined tool resources ToolOutput Function call response Best Practices Always dispose clients — Use using statements or explicit disposal Poll with appropriate delays — 500ms recommended between status checks Clean up resources — Delete threads and agents when done Handle all run statuses — Check for RequiresAction , Failed , Cancelled Use streaming for real-time UX — Better user experience than polling Store IDs not objects — Reference agents/threads by ID Use async methods — All operations should be async Error Handling using Azure ; try { var agent = await client . Administration . CreateAgentAsync ( .. . ) ; } catch ( RequestFailedException ex ) when ( ex . Status == 404 ) { Console . WriteLine ( "Resource not found" ) ; } catch ( RequestFailedException ex ) { Console . WriteLine ( $"Error: { ex . Status } - { ex . ErrorCode } : { ex . Message } " ) ; } Related SDKs SDK Purpose Install Azure.AI.Agents.Persistent Low-level agents (this SDK) dotnet add package Azure.AI.Agents.Persistent Azure.AI.Projects High-level project client dotnet add package Azure.AI.Projects Reference Links Resource URL NuGet Package https://www.nuget.org/packages/Azure.AI.Agents.Persistent API Reference https://learn.microsoft.com/dotnet/api/azure.ai.agents.persistent GitHub Source https://github.com/Azure/azure-sdk-for-net/tree/main/sdk/ai/Azure.AI.Agents.Persistent Samples https://github.com/Azure/azure-sdk-for-net/tree/main/sdk/ai/Azure.AI.Agents.Persistent/samples When to Use This skill is applicable to execute the workflow or actions described in the overview.