Add Microsoft Agent Framework integration with code-first agents and multi-agent workflows

Directory.Build.props

@@ -28,12 +28,17 @@
         <IncludeSymbols>true</IncludeSymbols>
         <SymbolPackageFormat>snupkg</SymbolPackageFormat>
         <EnableTrimAnalyzer>true</EnableTrimAnalyzer>
-
 		<TreatWarningsAsErrors>false</TreatWarningsAsErrors>
 	</PropertyGroup>
 	<PropertyGroup>
 		<NoWarn>$(NoWarn);CS0162;CS1591</NoWarn>
 		<!-- IL trimming warnings -->
 		<NoWarn>$(NoWarn);IL2026;IL2046;IL2057;IL2067;IL2070;IL2072;IL2075;IL2087;IL2091</NoWarn>
 	</PropertyGroup>
+
+    <PropertyGroup Label="PackageVersions">
+        <ElsaVersion>3.6.0-preview.4036</ElsaVersion>
+        <ElsaStudioVersion>3.6.0-preview.1297</ElsaStudioVersion>
+    </PropertyGroup>
+
 </Project>

Elsa.Extensions.sln

@@ -277,6 +277,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "data", "data", "{6D2A4421-A
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Elsa.Data.Csv", "src\modules\data\Elsa.Data.Csv\Elsa.Data.Csv.csproj", "{015646EB-EC33-4ADF-8417-B9D1A6B7CF06}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "agents", "agents", "{60A25F2D-634D-438A-87EA-F204677978BE}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -751,6 +753,7 @@ Global
 		{BEB35A25-5A80-4B56-A1EC-F005288CD11C} = {AAD61D93-7C78-42C4-9F37-2564D127A668}
 		{6D2A4421-A388-4BEE-BB11-D0FC32A80A10} = {30CF0330-4B09-4784-B499-46BED303810B}
 		{015646EB-EC33-4ADF-8417-B9D1A6B7CF06} = {6D2A4421-A388-4BEE-BB11-D0FC32A80A10}
+		{60A25F2D-634D-438A-87EA-F204677978BE} = {3DDE6F89-531C-47F8-9CD7-7A4E6984FA48}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {11A771DA-B728-445E-8A88-AE1C84C3B3A6}

src/modules/agents/Elsa.Agents.Activities/Activities/CodeFirstAgentActivity.cs

@@ -0,0 +1,71 @@
+using System.ComponentModel;
+using System.Dynamic;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Elsa.Expressions.Helpers;
+using Elsa.Agents.Activities.ActivityProviders;
+using Elsa.Workflows;
+using Elsa.Workflows.Models;
+using static Elsa.Agents.Activities.Extensions.ResponseHelpers;
+
+namespace Elsa.Agents.Activities;
+
+/// <summary>
+/// An activity that executes a function of a skilled agent. This is an internal activity that is used by <see cref="CodeFirstAgentActivityProvider"/>.
+/// </summary>
+[Browsable(false)]
+public class CodeFirstAgentActivity : CodeActivity
+{
+    private static JsonSerializerOptions? _serializerOptions;
+
+    [JsonIgnore] internal string AgentName { get; set; } = null!;
+
+    /// <inheritdoc />
+    protected override async ValueTask ExecuteAsync(ActivityExecutionContext context)
+    {
+        var cancellationToken = context.CancellationToken;
+        var activityDescriptor = context.ActivityDescriptor;
+        var inputDescriptors = activityDescriptor.Inputs;
+        var functionInput = new Dictionary<string, object?>();
+
+        foreach (var inputDescriptor in inputDescriptors)
+        {
+            var input = (Input?)inputDescriptor.ValueGetter(this);
+            var inputValue = input != null ? context.Get(input.MemoryBlockReference()) : null;
+
+            if (inputValue is ExpandoObject expandoObject)
+                inputValue = expandoObject.ConvertTo<string>();
+
+            functionInput[inputDescriptor.Name] = inputValue;
+        }
+
+        // Resolve the agent via the unified abstraction.
+        var agentResolver = context.GetRequiredService<IAgentResolver>();
+        var agent = await agentResolver.ResolveAsync(AgentName, cancellationToken);
+        var agentType = agent.GetType();
+        var agentPropertyLookup = agentType.GetProperties().ToDictionary(x => x.Name, x => x);
+
+        // Copy activity input descriptor values into the agent public properties:
+        foreach (var inputDescriptor in inputDescriptors)
+        {
+            var input = (Input?)inputDescriptor.ValueGetter(this);
+            var inputValue = input != null ? context.Get(input.MemoryBlockReference()) : null;
+            agentPropertyLookup[inputDescriptor.Name].SetValue(agent, inputValue);
+        }
+
+        var agentExecutionContext = new AgentExecutionContext { CancellationToken = context.CancellationToken };
+        var agentExecutionResponse = await agent.RunAsync(agentExecutionContext);
+        var responseText = StripCodeFences(agentExecutionResponse.Text);
+        var isJsonResponse = IsJsonResponse(responseText);
+        var outputType = context.ActivityDescriptor.Outputs.Single().Type;
+
+        // If the target type is object and the response is in JSON format, we want it to be deserialized into an ExpandoObject for dynamic field access. 
+        if (outputType == typeof(object) && isJsonResponse)
+            outputType = typeof(ExpandoObject);
+
+        var outputValue = isJsonResponse ? responseText.ConvertTo(outputType) : responseText;
+        var outputDescriptor = activityDescriptor.Outputs.Single();
+        var output = (Output?)outputDescriptor.ValueGetter(this);
+        context.Set(output, outputValue, "Output");
+    }
+}

src/modules/agents/Elsa.Agents.Activities/Activities/AgentActivity.cs → src/modules/agents/Elsa.Agents.Activities/Activities/ConfiguredAgentActivity.cs

@@ -4,21 +4,21 @@
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Text.Unicode;
-using Elsa.Agents;
 using Elsa.Expressions.Helpers;
 using Elsa.Extensions;
 using Elsa.Agents.Activities.ActivityProviders;
 using Elsa.Workflows;
 using Elsa.Workflows.Models;
 using Elsa.Workflows.Serialization.Converters;
+using static Elsa.Agents.Activities.Extensions.ResponseHelpers;
 
 namespace Elsa.Agents.Activities;
 
 /// <summary>
-/// An activity that executes a function of a skilled agent. This is an internal activity that is used by <see cref="AgentActivityProvider"/>.
+/// An activity that executes a function of a skilled agent. This is an internal activity that is used by <see cref="ConfigurationAgentActivityProvider"/>.
 /// </summary>
 [Browsable(false)]
-public class AgentActivity : CodeActivity
+public class ConfiguredAgentActivity : CodeActivity
 {
     private static JsonSerializerOptions? _serializerOptions;
 
@@ -44,30 +44,31 @@ protected override async ValueTask ExecuteAsync(ActivityExecutionContext context
             var inputValue = input != null ? context.Get(input.MemoryBlockReference()) : null;
 
             if (inputValue is ExpandoObject expandoObject)
-            {
                 inputValue = expandoObject.ConvertTo<string>();
-            }
 
             functionInput[inputDescriptor.Name] = inputValue;
         }
 
-        var agentInvoker = context.GetRequiredService<AgentInvoker>();
-        var result = await agentInvoker.InvokeAgentAsync(AgentName, functionInput, context.CancellationToken);
-        var json = result.ChatMessageContent.Content?.Trim();
-
-        if (string.IsNullOrWhiteSpace(json))
-            throw new InvalidOperationException("The message content is empty or null.");
-
+        var agentInvoker = context.GetRequiredService<IAgentInvoker>();
+        var request = new InvokeAgentRequest
+        {
+            AgentName = AgentName,
+            Input = functionInput,
+            CancellationToken = context.CancellationToken
+        };
+        var agentExecutionResponse = await agentInvoker.InvokeAsync(request);
+        var responseText = StripCodeFences(agentExecutionResponse.ChatMessageContent.Content!);
+        var isJsonResponse = IsJsonResponse(responseText);
         var outputType = context.ActivityDescriptor.Outputs.Single().Type;
 
-        // If the target type is object, we want the JSON to be deserialized into an ExpandoObject for dynamic field access. 
-        if (outputType == typeof(object))
+        // If the target type is object and the response is in JSON format, we want it to be deserialized into an ExpandoObject for dynamic field access. 
+        if (outputType == typeof(object) && isJsonResponse)
             outputType = typeof(ExpandoObject);
 
         var converterOptions = new ObjectConverterOptions(SerializerOptions);
-        var outputValue = json.ConvertTo(outputType, converterOptions);
+        var outputValue = isJsonResponse ? responseText.ConvertTo(outputType, converterOptions) : responseText;
         var outputDescriptor = activityDescriptor.Outputs.Single();
-        var output = (Output)outputDescriptor.ValueGetter(this);
-        context.Set(output, outputValue);
+        var output = (Output?)outputDescriptor.ValueGetter(this);
+        context.Set(output, outputValue, "Output");
     }
 }